Watch shorts, our quantum lab tour and interviews with academics.
'Is the Future Quantum?' Panel hosted by Jim Al-Khalili
Well hello everyone, good evening and welcome to this latest University of Sussex ‘Ask the Experts’ series. I’m Jim Al-Khalili I'm a Professor of Physics at the University of Surrey, not to be confused with the University of Sussex, although a lot of people do.
Surrey and Sussex, however, the two universities have very close ties, I know a lot of the people in the physics department, and indeed the panellists this evening. The University of Surrey and Sussex are both part of what's called The South-East Physics Network SEPNet - in fact both universities were among the six original partners of that network, which involves all physics departments, now, among ten universities in the southeast of England.
Anyway, this is the second ‘Ask the Experts’ online event run by Sussex, the first one was back in March, and that was on Covid-19. Now, the aim of these events is to showcase and give an insight into some of the University of Sussex's most important areas of research and which will - and do - have great societal impact. Now the Ask the Experts series brings together panellists, a panel of world leading experts in their field from the University of Sussex, so thank you very much to the panellists this evening who've made their time to be part of this debate about all things quantum. Okay well not all things, but I think there'll be a theme, I imagine, running through the next hour or so.
The way it works is that I will introduce the panellists they'll say something about their work and their interest in their research for a few minutes each and then we'll come to the Q&A and you can get to ask them questions and questions have been flooding in already.
So basically, the topic is general quantum mechanics and its applications but in particular the new technologies that are evolving, what we call quantum technologies, that are emerging from current areas of research. Now if you'd like to ask the panel anything, then please add your questions into the Q&A bar whenever they occur to you, right. These will then get transferred and we will deal with them when we come to them later on. A lot of very organised people have sent their questions in advance, of course. Okay, so without further ado, I will introduce our four panellists for this evening.
The first panellist is Professor Winfried Hensinger, who is Head of the Ion Quantum Technology Group at Sussex. He is also director of the Sussex Centre for Quantum Technologies, and co-founder of Universal Quantum, which is a full stack quantum computing start-up company, and he serves on the EPSRC’s Physical Sciences Strategic Advisory Team. EPSRC is the funding council which funds the research in quantum technology, so Winfried Hensinger- welcome and over to you to say a few words
Thank you, Jim, for this lovely introduction. So, I came to Sussex in 2005 and that was a time when people kind of rolled their eyes when we were thinking about quantum computers. Now let me start with, What is a quantum computer? Quantum computers are machines that can solve certain problems where even the fastest supercomputer might take billions of years to calculate and: How does it work? It can use such things as teleportation and superposition of an object that can be in two different places at the same time. Now, this is tremendously hard, to build a machine that can do these things. So, we started in 2005 trying to develop a machine like that, and what we use is individually charged atoms or ions and we hold them inside a vacuum system and so people used this type of technology before to build very stable clocks to define time and to define frequency, but then people got the idea we can hold and control these atoms so well and they can control the quantum effects with such precision, that we can use them to build such quantum computers, and so we started in 2005 with a fantastic team of really outstanding scientists and we worked very, very hard and one of the things we started developing is the idea of using microwave technology to do calculations inside this quantum computer.
So previously people used pairs of laser beams, now that works really well when you have a handful of quantum bits. But imagine you need a million quantum bits, imagine you need to manipulate a million quantum bits and you'd have to align all million pairs of laser beams, so we invented a new way to use microwaves and that allowed us to come up with an approach to quantum computing: we simply apply voltages to a microchip in order to execute calculations inside this quantum computer. In 2018 we led an international consortium from Google and many leading universities and we published the first construction plan of how you go about building a practical quantum computer that could host millions of qubits and would be capable of solving some of the really important problems. To put this into context, machines you have currently available at Google, IBM hold maybe 70 or 80 qubits and so 2018 was a big year because then we also started getting together a company which will take practical steps to build such machines and so I am actually also in my job in a quantum superposition of leading a research group at Sussex, but also being chief scientist of this company where we do the really hard engineering in order to build practical machines. Now, I think I’ve got pretty much a dream job because when I started, I wanted to be the Science Officer on The Enterprise, that was in primary school and I kind of think I’m very close to that job. I use teleportation in my day to day job, I work with the most outstanding scientists you can imagine, I’ve got a lab full of the maddest and craziest machines. All with one goal: in order to build machines that can solve problems we couldn't solve before that might mean creating pharmaceuticals, create new materials and do things we couldn't do any other way before. But that's the big mission - there's also the day to day and I want to show you something which really excites me now. So around five minutes ago, I got a text from my students and I want to show you this, I don't know whether you can see this, but see here on my phone a string of ions and they have managed as of around 15 minutes ago to hold ions – this is one of the most advanced quantum computing prototypes – and managed to demonstrate the first holding of a string of ions, which is a really, really, fantastic step.
So I’m very lucky man work in an area where we can really do so many amazing things and I think maybe I want to show you a little bit of the enthusiasm. Because this is really new for and fantastic emerging technology and I think I’m very lucky to work in this field so maybe that's a good introduction and I’m very happy to have lots of questions later.
Thank you very much Winni that's a very nice introduction actually and I’ve already got questions to ask you, but I won't hog the question time. We leave it as we have so many questions coming in that we don't need me adding to them as well, so thanks for that. Ok, so now our second panellist is very brave, because she is a PhD student, so this is Shobita Bhumbra. Welcome Shobita, she's studying her PhD in quantum physics of ultra-cold atoms, this is within the Quantum Systems and Devices group, which is part of the physics and astronomy department at Sussex. So Shobita, welcome and maybe you can say a few words about what your PhD is on.
Thank you, Jim yes, I’m a PhD student and I work with Peter who we're going to hear from next and we work on a very different side of quantum technology than what we just heard about from Winni. We work on quantum sensors, we try to develop quantum sensors so, what I mean when I say quantum sensors is, we have a system that has some kind of quantum property or effect that we're going to try and use to measure something. In my PhD and in my work I’m trying to measure magnetic fields and I use, as Jim mentioned earlier, I use ultra-cold atoms and it's by getting them so cold that we get the quantum property that we use to measure the magnetic fields and this has a huge range of applications from biomedical research to material science and because of the huge range of applications, we actually need people from all sorts of disciplines to help get this technology working towards those specific applications and I actually don't have a physics background doing this physics PhD. My background is that I did my undergraduate degree in biochemistry and genetics and since then I have also done some electronics work and I guess part of what got me excited and invested in doing this PhD is the collaboration and the mishmash of all the different technologies and disciplines that you need to get it to work, I’m actually working with physicists and also a materials scientist here in just our little lab, our little experiment alone, and I’m sure Peter’s going to tell us more about the other things under his umbrella.
Thank you very much Shobita and yes - clearly a sign that probably the exciting research that goes on in this field is done by people like you who are interdisciplinary having a background in genetics, electronics, you know, bringing all these different ideas together so very exciting time. Well as you say your supervisor, your boss, is our next panellist, that's Professor Peter Kruger. Now Peter is the Research Professor of Experimental Physics and Head of the Quantum Systems and Devices Research Group, as well as the Founding Director of the Sussex Program for Quantum Research, Peter welcome.
Yes, thank you Jim and thank you Winni and Shobita, for your very enthusiastic introductions to what quantum is and can be and has been, and I think it's certainly worth asking the question is the is the future quantum? I think we can already see from what those two have told us that the present is a very exciting time for quantum and of course the past has been, and I have certainly believed for all of us, the future is quantum but maybe for all of you I’m very happy to have to see that almost 300 people are joining us today.
So, a little bit about myself, so I started to be interested in quantum physics, quantum in general, when I was in high school student in the early 1990s, I didn't understand anything about what quantum was then and I don't really know why I was interested, but it was fascinating to see that there was so much talk already then about what quantum is a lot of it seemed to be a big intellectual challenge to understand it, because it was a synonym for things that cannot be understood, and I think we should be far away from that now. Anyway, I did go to university in Berlin at the time, by the way, the place where quantum was first concepted by Planck 100 years earlier, and went to my first quantum theory lecture - still didn't understand anything and was a bit taken aback by that but, I noticed that quantum physics had been very important in explaining things that we have been using for quite a while now from lasers to medical imaging, MRI, transistors and electronics, even classical computers wouldn't exist in the way they do without quantum physics, so that was very important but I guess a bit of a relief was then to see that, actually, no one had really understood quantum fully, I think. I think it was Richard Feynman who said, famous quantum physicist, of course, “If you think you've understood quantum physics, you only prove that you have not understood anything.” So that was a bit of a relief after that first lecture but, but what was fascinating then, in the late 90s, was when I saw my first real research experiments. Quantum teleportation was the first experiment, I saw that what were some of the old more philosophical debate topics between people like Einstein and Bohr already in 1930s about what it means that particles are also waves, and waves are also particles, had suddenly become accessible in experiments and that was important, that actually drove me to from wanting to become a theoretical physicist to ultimately becoming experimental physicist because experiments could let me say something about this, the experiments had become so good, the control of quantum systems was possible, and to such a high level that these old philosophical questions could suddenly be answered, at least in part, and we gained a better understanding of the foundations of quantum physics. But what is more, is to say that in the last 20 years and so on of my active research career, why these fundamental aspects are still important; we still trying to understand quantum systems, better than before and make them more complex, build them up from scratch and see how particles interact in different dimensions and whatnot. But the techniques that have become available have allowed us to turn quantum physics into quantum technology and we're trying to bring it outside the laboratory and that is why we call it quantum technologies now. Wini’s fascination about computers is one aspect, but there are many others - the quantum sensors Shobita mentioned a bit and other aspects of communication and secure processing of information and so on. And all this, this has now become possible and this, I think, is the reason why we're having this debate and why so many people outside of the physics domain become interested in this. And, and this investment flowing in start-up companies and so on, you've heard about it so that's quite important, and in our field we do a lot in our group, we do a lot of this work now, and this relates largely to magnetic field sensing. as Shobita mentioned, but it has many applications from the very microscopic understanding of minute current flows and materials in electric vehicle batteries, up to understanding the small magnetic fields that exists outside the human brain, where we can we have just in our lab been able to detect the difference of a person being asleep and being awake or, rather, having the eyes closed and having the eyes open, not through looking at the eyelids which would be too easy, but by looking at the actual brain activity that is manifesting magnetic fields that we can measure outside the human brain so interesting stuff ahead, I think the future is quantum not only for us, but for many and I look forward to any questions that all of you might have, thank you very much.
Thanks very much Peter yes, you're right, quantum technologies isn't just about applications that can be commercialised, it's also about actually testing some of these really deep profound questions that in the past, have just been the domain of philosophy. Now we're finally able to do experiments, build devices and make measurements that actually answer some of these deep questions. And I think you know some of the questions coming in this evening are going to be speaking to that. Okay, so our fourth panellist is Dr Alessia Pasquazi, who is a Reader in the Department of Physics and Astronomy and Director of the Emergent Photonics Lab. She's a Researcher in the Sussex Centre for Quantum Technologies, she's also Editor - or one of the Editors - of the Scientific Reports Journal part of the Nature Publishing Group: Alessia, welcome.
Jim, thank you very much, and thanks to everybody for listening to me today, so I am the photonics expert of the group. So let’s start and start to say, what is photonics about. Photonics is the science of light, so you may wonder why I’m not calling it optics because you don't call your computer an electrical machine, you call it an electronic machine and in this word electronic we put the concept that this technology is based on a specific particle, a specific quantum particle, that is an electron.
At the same time, the word photonics takes in the concept, or the fact, that we have a technology that is based on the basic quantum particle of light, that is the photon. So in photonics ,you can do many things, it’s one of the cornerstones of quantum technologies that lasers, that we use every day from surgery to telecommunication and internet communication, everything in fact is really, really, based on these types of technologies. But, like everybody else here I’m focusing on a specific problem for what will be our future technology and I specifically work at building a portable atomic clock now, this is a very, very specific type of type of problem, but is extremely, extremely, interesting. Because the reason why clocks are important, is we can do many things with clocks, so you have to think that the internet, all communications, they all work because they are in sync with electrical energy that you get your in home and work because it's very, very well synchronised. So all these things are really relying on the performance of common technology that we have so far: relying on a very good clock. But in a little bit more of an interesting twist, if you have very good timing and if you can take it with you and take it around with you can also navigate and say where you are without the need of, for instance, the GP. Now, the GPS is actually working with many atomic clocks that are above our head, but if you could have your atomic clock here with a little help from the quantum sensor that many people like Peter and others are developing, we could go and navigate without anything else. So I’m sorry for spoiling the fun of Pokemon-Go, as there is no more hacking to do, but also we could have much more security for managing self-driving cars, so really it's a technology that would enable many things.
So how do we put a clock on a mobile phone, like this one? That will be a little bit of some long way to go, but the important thing is to make small and efficient the two main parts of the clock. As in every clock, if you think of our grandfather clock, an atomic clock is done by reference to the counter so if you think of the grandfather clock, the reference is the pendulum. So, in a pendulum, in the case of the best clock in the world, it oscillates at the frequency of light, so this is something like 1/300 terahertz, and nothing can count so fast.
So, what can we do, is, we need to build up a reaction here and the beautiful idea that John L. Hall and Theodor W. Hänsch had, and they got a Nobel Prize in 2005 for this, is that instead of counting the frequency of light, if you are able to synchronize perfectly the pulses of a laser with this frequency, you can simply count the parts - and they solved an incredible problem. Thanks to them we have clocks that are accurate to 10 to the minus 16 second and we are very lucky also for another point, because here in Sussex we have Matthias Keller, who unfortunately is not with us today, but he's one of our leaders, and is capable of fitting these portable references in very, very small boxes - something in a box like that. (demonstrates small box) Me, myself, I’m almost able to fit it in a mobile phone, so how we do that? We need to make a very good pulsed laser, but when you want to achieve that you have to start to remove all the bits and pieces that common lasers have, so we are now really working at the minimum of physics possible and we are using actually a very interesting phenomenon, a sort of natural phenomenon, to get out these pulses from a laser. This is the same phenomenon that the muscles of our hearts use to have a pulsing heart. The pulsing heart works, because all our muscles are synchronized together, and they keep the periodic beating that you're feeling there. And the same thing, this type of phenomenon that is called synchronization, is used by the cicadas to sing all together, they do not know what is going on, they just sing together, because they are in sync. And so, I have a cup, to show my results (demonstrates cup). The theory is that we are able, inside the very small chip, to fit the form, we are able to synchronize all the modes of our laser as you see here, so this is the real spectrum that we had, all these lines on multiple lasers and they are in sync, so what it means is that if you take, if you measure the light coming out of it, you will see pulsing and you can use these pulses to measure the frequency of the super cool clock that Matthias is building basically downstairs my lab. So, this type of synchronization phenomenon is called an emergent phenomenon, it is very much a similar type of phenomenon that you find everywhere in physics, so that is why my lab is called the Emergent Photonics lab, because we work on this type of the physics. We call it E.P club for short and we will need it to be a sort of good luck name, we need a little bit of good luck, but I think that eventually it would be super epic to have a clock that is accurate with 10 to the minus 18 second that basically works like this synchronization of beating.
Thank you very much, Alessia. Ok, so I want that mug, an then I want a clock this accurate and better than one in a trillion, for the seconds on my smartphone. So this is the future, this is how the quantum technology really comes into our hands and it’s amazing stuff. Okay, well look, this is an ‘Ask the Experts’ event, right, so we've heard from all the four experts - let's get to ask them some questions. So, questions have been flooding in, I’m going to try and ask as many as I can and I think what I’ll try and do is aim questions at particular panellists but, of course, if other panellists feel they want to sort of chip in and add something, please do, but my advice to my panellists is let's try and get through as many questions as we can, I don't want us to sort of get bogged down for 10-15 minutes just answering one question, because there are just so many here. Unsurprisingly, there are quite a few on quantum computers so let's deal with two or three of those first. So, this is the first question, it’s from my namesake, from another Jim, and I think we…thank you Winni, for turning on your video because I’m going to come to you. So, Jim asks: is there any evidence that quantum computers are faster than conventional computers in practice, not just in theory? You know you're muted, though still.
Excellent, so, the advantage of quantum computers is that they really utilize an entirely different working principle to conventional computers and in a way it makes use of the principle of superposition, and that means that a bit rather than a zero or a one, a bit can be zero and one at the same time. Now building on these rather strange quantum phenomena, you can come up with a new type of algorithm, a quantum algorithm. And, for certain problems, to speed up is just tremendous and what does that mean: “a tremendous speed-up”, it means that, for certain problems, a problem that would take even the fastest supercomputer in the world millions of years to solve, a quantum computer may solve in minutes or days. And so these problems are well known - a famous one is breaking RSA encryption. For me, that's not very exciting but it’s a famous application, creating new pharmaceuticals, understanding chemical reactions or doing optimizations for some financial problems - portfolio optimization is a very important application. Also simulating flows and it means, for example, making better aircraft wings, one could even imagine understanding weather forecasts better. So there's a whole range of applications and the development of quantum computers goes hand in hand with the applications. With the app development of new applications this is a really exciting time where we see every day new applications being developed and obviously we also work very hard to build practical quantum computers that can tackle these.
What you're saying, Winni, is that there are there are conventional tasks that our current non-quantum classical computers do, which we will continue to use because they do them very well, but there are still these certain specific tasks that quantum computers are going to be particularly well suited for, and they can do them much more quickly and much more effectively than any supercomputer we have today.
So, I don't think you will have this on your desk, it's really for particular applications.
Right, I still want one of my desk though, I mean come on! Okay, so the next question is from Professor Sir David Clary FR who asks: the idea of a quantum computer has grabbed the imagination, but there's so much hype and speculative claims for imminent breakthroughs, some say that major new developments in material science are needed to achieve a useful quantum computer, would you agree? Maybe Peter, can you say something to this.
I can try, I think I would agree, I think. Even though we've had a lot of tremendous development and, I think, in the context of the previous questions we've seen so much success in the early development of quantum computing, yet I’d say we're still early days, and in the sense that there are still multiple platforms that are considered for this, so that could be a solid state-based platform, it could be an ion-based platform like Winni is using. or it could be something else and all of these platforms, with which have demonstrated early operation of the principles of quantum computer work, which is a great milestone to have achieved, they have to be scaled up to much larger sites and I’m fascinated by Wini’s project to do precisely that. Others do the same and the big computing companies all got onto this, so IBM is doing this, Microsoft is doing this, Google is doing this, so all have their projects of scaling up quantum computers in various platforms and have various ways of realizing this quantum qubit. But when you mentioned it in practice, all of them have to deal with how that works and how, when you make things big and multiplied many times over defects become more and more important, and I think materials, just like we've seen in the semiconductor industry for classical computers that over the last, I don't know, fifty to one hundred years has been developed so much, material science and how to make materials better has always played a tremendous role, and I think it’s absolutely essential here and, yes, this is one of several developments that we need to control better and that's also where this interdisciplinarity comes in, all the different fields have to work together to make this big dream a reality. Winni, would you also agree?
Yes, absolutely, and to maybe delve a bit more into the question that this is really about one particular platform, the idea to build quantum computers, made out of silicon chips, where the qubit is embedded inside the silicon chip - and indeed David Clary is very right and we need more advances in the material sciences to make such a quantum computer happen - the advantage would be, might be, a very small quantum computer you could have eventually on your desk but there, we really need many more years to develop this. It’s kind of cheating the system a little bit by using silicon microchips, but the qubit is not embedded inside the microchip, it actually levitates 100 microns above the chip, and so that makes it easier to isolate the qubit from the environment and again releases the pressure on making advances in material science to build a practical quantum computer.
Thank you. So before we move on away from quantum computers, there may be others coming up later, but here's another one, maybe this one's for you, Alessia, because you talked about the technologies that are emerging with quantum sensors and more and more advanced atomic clocks and so on. The question is this; is quantum computing - but I guess it applies to various other kinds of technologies as well - is quantum computing like nuclear fusion: always 40 years away. In terms of the time scale of these technologies, how far away, are we really from realising them?
I love to talk about how and where we are with quantum computers with Winni here. I can blame it on you! So I think that the general question on quantum technologies is that there are some parts of the technologies that are already practically ready compared to some of them that are a little bit more far away, so I will take the perspective from another point of view, from my point of view, and tell you that photonics is perfect, because we are ready, we are ready to enter the chips and to stay with electronics or all the bits and pieces that require photonic mixing and those technologies are much, much closer for us to arrive right there. All the bits and pieces that instead are required to really handle the fermions, to take the other side, so to handle the ion, the electron, to handle those particles - that I will leave it to my colleagues to comment on that. Those are really the technologies that are pushed at the moment, but we need to push them at a certain point, because we need to see the design somewhere, we need to see the bits there, and so what I really love with Winni’s work is that he has the bits to build the technology with the processing of silicon, so like my clock, like my results here, that silicon ready, that is important. Winni’s is silicon ready that means that when he's will be ready, it will be able to print out his results in his computer on something that can go mainstream, and this is the same for us, so when we will be ready to do it, we will be able to print this thing together with electronics so we have a lot of thinking on this.
Do you agree, Winni, that we're closer than many people think, because we hear a lot in the in the news of you know quantum supremacy and all this sort of nonsense about you know who's actually finally built a quantum computer and then you realise maybe it wasn't quite what we had hoped for, how far away, would you say?
So I’ll make this very personal: when I started in 2005 for the University of Sussex many of my colleagues, and I’m not going to name any names, or people in general, rolled their eyes when I said “I’m going to build a quantum computer” and the words quantum technology, nobody even used that. And things have changed, there was the national quantum technology programme in UK which was organised, and suddenly there was a lot of funding to make things really happen. And then in 2018, maybe a lot of breakthroughs happened, and so I think the last few years have really shown that quantum computing is moving fast forward and we see that major companies are engaging. Like, nearly any financial company will engage now with quantum computing and they don't do that, out of naivety, or because they feel they need to throw a bit of money around but because they know it is happening, and it is happening, you see machines that can do useful things. All the proof of principle phenomena have been shown and as Alessia pointed out, we are now setting out to build silicon microchips - we do this as part of my company, Universal Quantum, where we now hold ions above to silicon microchip. And do real world calculations, so we are now really moving away from simple academic work to build particular machines. And this is something I want to say also, maybe for the coming generation, it could not be a more exciting time to get into quantum technologies, because what we're going to see is a real technology revolution, where we are going to see these technologies coming to fruition, and so I think it's a fantastic time for quantum computing and quantum technologies in general.
Thank you. Shobita I want to come to you and I’m going to - I will be asking you a more technical question later on, don't worry about that, but I want to start you in gently because there's a nice lovely question here asking; what's it like to be a research student in such a cutting-edge field?
I think I’ll be very honest with my answer.
That's always good.
I think sometimes it is exciting, but obviously you're working here so sometimes it's mundane and sometimes it's frustrating, I think, as in any research position, but I found that because there are so many different disciplines here and everybody is very understanding of your ignorance in certain areas, and will take the time to help you catch up with things because they're having to do the same thing in different areas, and so I feel very thankful, very lucky for that and I do very much enjoy working here.
A question here from Maya who asked, can you discuss quantum technologies applicable in healthcare? Peter, would you maybe like to answer that one.
Yes, happy to and the others can chip in if they want to add, but I think that there is sort of the short term and the longer-term answer to this and for the longer term we've already heard about drug design and, you know, pharmaceutical companies thinking about quantum computers and how they can influence therapies, perhaps in the future - that I would classify as more long term. On the short term, however we've already seen that quantum sensors outperform classical sensors in numerous modalities of sense and in particular, of particular importance for the biomedical imaging is magnetic sensing, we know that MRI is one of the success stories of more recent medical instrumentation and that's a medical resonance imaging based on, sorry Magnetic Resonance Imaging, so that's already based on magnetic fields. Improvements on that, for example, to get away from these very large, heavy expensive superconducting magnets in MRI can be facilitated with ultra-low field Magnetic Resonance Imaging, and it's now being tested in the laboratory so we will probably see that soon in medical practice. The other area that I’ve been lucky enough to work in myself is magnetoencephalography. Now, here we have something where quantum sensors are so sensitive that we can passively just listen to the brain, we don't do what we do an X-Rays, where we will try to radiate the brain with something from the outside and measure what comes out the other end we don't try to stimulate it like we do with the Magnetic Resonance Imaging, conventionally, but we simply listen to the neurons firing in the brain and that’s electromagnetic and it creates a small magnetic field that even exists outside the brain. We can pick it up and measure it and I think that is one of the fascinations for me that already today, we have this and we just have to go through practicalities and approvals, and so on, so we have to be interdisciplinary and will then extend to lawyers - not my domain – but this is where we are, so I think we really are there for medical applications, it’s very fascinating.
Very fascinating and very exciting. Another question: actually, this this one for you, Alessia because it's exactly following on from what you were talking about it's a question from Ashley who asks: I read something about the use of quantum technology to provide super accurate sensors, how practical is this, or is it purely theoretical? Well, you've talked about it, but the example here that Ashley gives is lifting an atomic clock slightly changes the gravitational pull on that clock, allowing height to be measured and quantum interferometers can measure minute variations in gravity, so utility companies could find buried pipes or for oil companies to find oil or gas pockets, is that something that's being looked at?
Of course, yes, yes, yes, this is so, this is one of, basically, the reasons why we are really going ahead with quantum sensing because now with this micro scale, this very small deviation, they are very much seen in all quantum types of sensors and one point of this is that we will be to make them small and portable, so that is all that this story is about basically, so in the first quantum technology programme, the first round, had a lot of focus exactly on doing these things, these very small portable devices and it has been impressive just to see how much of the progress has been done with that. Again, similarly, so they are now things that can be transported, so you can now fit them and bring them outside the lab now and really, there the push will be to put them on some electronics and then we will see the interesting, the interesting thing. I wonder, maybe Winni you want to comment on that because I, I wonder how much of your say, of what you or Peter are really working in in putting these devices on chips and traps in integrated systems, so maybe you can give a better perspective in terms of number on when we will be there with this.
So, this is very much the centre of the company we've founded at Universal Quantum, so I started leading a research group building practical quantum computers and so you build proof of principal machines and the chips you make, you make in university clean rooms, which kind of like is all a bit of a, well, these chips aren’t very high yield or very reliable and so now in the company, we make these fully integrated silicon microchips with have the advanced features and we do this in foundries rather the university clean rooms so that means that the yield and precision you make these chips with are just amazing. So the next step is obviously to now deploy these chips in practical quantum computer prototypes so that's what we are working on. The timescale for that is maybe three to five years until when we have the practical first quantum computers that can do useful and interesting things. The time scale to build machines that can solve problems, really, really hard problems we're still looking around ten years but it's worthwhile, because if you think about some of these problems if you can solve them it's in a way, really disruptive, because it changes the way we do things, I mean, maybe to the Google search algorithm and other disruptive technologies.
Just checking the time and it seems to go by very quickly, so we should move on, Shobita a question for you, only because I know you've come into this field, from a different background; How do you explain why a non-physics background investor should care about quantum technologies, do they try to understand what exactly makes it different or are they just going to trust the scientists? You know, how is it that you're convincing these people, how is that different say from applying for research grants within the field?
This technology, especially, you know, what I’m working in, the sensing and that can be applied across fields like, say, a scanning electron microscope or an MRI machine is applied so broadly and has assisted in so many different ways. That is a similar place to where this sensing technology can be. We're all talking about these quantum technologies and getting very excited about what the future might hold but for someone who doesn't know the word ‘quantum’ but knows that it's weird and it's difficult to understand, and they may have heard of, you know, Schrödinger's cat in the box and nothing else, how do you inform them that quantum technologies are something different, something fresh, something that we need to invest in. I think it's not so much the storytelling actually in the end, especially when you talk about the transition from the money coming from some government funds and private sector investments. I think here, you really have to demonstrate milestones, that these things work, and I think it's very important that we don't only talk about the quantum computer, even though it’s as exciting as it is, because in the quantum sensing area in particular, we have applications today we have measured brain signals with these things, we have improved our clocks to measure one part, and I don't even know what ten to the 18 is and how many trillions, it is a huge magnetic field that is a trillion times smaller than that of the earth, which is in itself small enough that it took a long time for people to measure. So I think demonstrating what we can do and showing people in laboratories and outside laboratories in particular, I mean I remember one meeting where we showed that we can cool atoms to essentially zero temperature. A gas of atoms to zero temperature just simply by shining lasers on to it simply, of course. Not in a lab, but inside a showroom of an industrial trade fair or in a meeting room in the European Commission in Brussels, this shows, this convinces people. When you demonstrate that things work or Winni shows trapped ions to people that they can hold in their hand, I think these things matter and that's where we are at, and I think that's why we see so much push in the field at the moment.
Thank you. Winni a question for you: Will quantum computing render current forms of ryptography useless and will it allow previously encrypted content to be read? Is society prepared for having a universal quantum computer?
Yes indeed, so one of the very famous applications of quantum computers is that quantum computers in principle can break RSA encryption. Now I should know that that's probably one of the hardest applications! In terms of how to be a requirement for quantum computers, there's going to be many applications which will become available before we are going to break RSA encryption. Now I want to add a little side note: in 2018 we published the first construction plan of how to build such a machine, and we calculated how big such a machine would need to be, and this machine would need to be nearly the size of a football pitch, it was a huge machine, and I want to go back to an earlier question: if somebody had said, so this is always forty years away. Recently we made some theory advances, significant theory advances, and we can now build a machine like that capable of breaking RSA encryption, size four meters times four meters. Now again, this is still one of the hardest applications and it's still at least 10 years away so please relax, nobody will immediately break your encryption, however data which is now safe today in 10 years’ time or 15 years’ time may be able to be read so that's certainly something we need to think about. Right now, people are already working to devise new ways to encrypt which are even now, not to be broken in by a quantum computer, we are right now working on new ways to encrypt information, making our information resilient to quantum computers, but I should maybe add as a final note that, with the introduction of quantum computers, we also need to think very carefully about how we deploy them in society, and we need to think about regulation and societal implications - that’s certainly where we are starting right now and it's very important with, like any technology, like AI, to start now to do this work, so we feel we can live safely and take maximum advantage of the opportunities and promises of this new technology.
Thank you, okay, well I think we've got time for a couple more questions, and I say a couple more, because these are questions I want to address to all four of you so I’m hoping you're going to give me snappy 10 to 20 second answers only, otherwise we'll run over time, the first one is this: If you could magically have a perfected quantum technology today what would you choose? Peter, go on I’m just going to look at you.
Right, so I mean I am fascinated by the possibility of turning sensors into cameras, so I would like to have a camera that sees magnetic electromagnetic activity or even gravitational fields over large areas with high resolution.
I think eventually everybody would like to see something related their own baby right, so, and I think it will be great, to have these little clocks in our computers because we will have a lot of very good things also for the telecom and other good stuff.
I think I’m going to be equally as boring and selfish and say, I would like my PhD project to work!
Absolutely understandable. No I also really quite like the brain imaging that's going on over here that I’m not working on, I think that would be amazing to see the applications of that working. Great, okay Winni over to you, what, I wonder are you going to say?
So, with my head on, as Director of the Centre of Quantum Technology, I’m going to say the most diplomatic answer and say that all these quantum technologies are simply amazing, but I will tell you one more thing, and that is, I will build a quantum computer not tomorrow, but it will happen and that's obviously where my personal excitement comes in. But I also want to advertise all the other fantastic quantum technologies which are equally fantastic and really one more one more pitch for everybody who is going to get into physics, this is the time to enrol in a physics degree, this is the time to develop practically quantum technologies.
As you've heard here, you know quantum mechanics in any case is a very difficult subject and developing some of these technologies is incredibly fascinating but also incredibly complex and we can't possibly do it justice in this just short one-hour event, but hopefully it's given you a flavour of the sorts of things that are going on and the sort of research that's going on at the University of Sussex today. I’d like to thank our four panellists Winni Hensinger, Shobita Bhumbra, Peter Kruger and Alessia Pasquazi. Thank you all for your very clear and concise answers we could have gone on for much longer, of course. Please look out for the next ‘Ask the Experts’ event which will be on the theme of consciousness, and that is due to take place later towards the end of this year, but you will be hearing announcements of it in the coming months. Thank you everyone for joining us, thanks again to the panel and have a very good evening. Goodbye.
The Emergent Photonics team on portable atomic clocks
- Video transcript
Precision timing is critical in many sectors. We use it to navigate with GPS and to synchronise the traffic on our phones. With a portable atomic clock, our communication could go faster and we could navigate without the need for GPS. Let’s see, today, why we are a step closer to this - come with me.
What we did, is to improve the part of the clock responsible for counting by about 40 times the state of the art and this is key to replacing the current generation of GPS technologies in the next 20 years.
Juan Sebastian Totero Gongora
Optical atomic clocks lose less than one second every ten million years, but they are additionally massive devices weighing hundreds of kilograms. We need something much more compact, that can be integrated in a chip as small as this (shows size of chip). If you want to build a clock, the first thing that you need to set is a precise reference, which dictates the ticking. Think for example, of the pendulum of a cuckoo clock. In an atomic optical clock, the reference is set by the electro-magnetic oscillation of an atom contained in a small chamber. The challenge, however, is that those oscillations are extremely fast, more than one trillion per second. How can you count so fast? Well, the solution is using a regular train of laser pulses, which is called a frequency comb. The frequency comb acts as a reduction, here, for the optical clock, to get to a reasonable speed that can be counted more easily.
As part of the UK Quantum Technology programme here at Sussex, we are developing a technology to produce a comb with a device we call a micro-resonator which is a tiny ring of glass with a section of microns, different from standard lasers, which can produce light only of a particular colour, here, only a small piece of glass can, in principle, produce all the colours we want by mixing photons together. This seems unusual and we normally do not experience it. The trick here, is to confine the light in a tiny volume, like a glass cavity.
Microcombs are based on special waves called Cavity-Solitons. Solitons are very robust waves. Tsunamis, for instance, are water solitons, that can travel for incredible distances without being perturbed. After the earthquake in Japan of 2011, some of those Tsunamis reached the coast of California. Instead of using water, in our experiments we use pulses of light, confined in a small ring of glass. Cavity-Solitons take their energy from a reservoir wave. Standard approaches require a huge reservoir, so for old microcombs, it was like using a huge surf wave to keep alive a soliton as big as the surf board. The efficiency of those systems was below 5%.
By placing the glass ring inside a fibre laser, which is the same kind as used to bring the internet into our homes, we can eliminate the reservoir wave, keeping the soliton alive with the energy of the laser. Technically, this king of pulse is called a Laser Cavity-Soliton.
Here, at the Emergent Photonics Lab, with our colleagues at Sussex, we are developing all the bits and pieces to produce portable atomic clocks. Think about an atomic clock that could actually fit in your laptop or your mobile phone. Think about a self-driving car, self-aware of its position in the world. This is the future we are working on now.
Dr Alessia Pasquazi interviewed for She Can STEM
- Video transcript
Thank you for your time, and I was wondering if you could introduce yourself, please.
Jessica, thank you very much. So, first of all, I want to thank you for this opportunity and it's great to talk to you, to talk to the nice students that we have in Sussex. So, my name is Alessia Pasquazi and I'm a reader in physics here in Sussex.
And I know Jessica and many people from here because I've been teaching for many years at lab one. I work in optics and photonics. That is an amazing science where we can play with light; that is something that I always liked to do. Even when I was young, I remember exactly - I don't know if you were playing with lamps and lenses and make all the images of the room around, right?
There's something magical that sometimes happens, so this is I remember, playing with this stuff. I was not that young, but a relatively young age. And look at the beauty of the optics and of the images forming in the dark where you could do all these interesting things. And then, eventually, I started to study properly: electronic engineering in my case. So, I don't come from physics, I've done a jump, and, why I ended up doing electronic engineering because I liked maths. So, I have always been a girl that liked to do the numbers and these things, but I didn't know too much about general physics we studied it in Italy, but I had a professor that was the teacher that was teaching us maths and physics in my high school and she was a mathematician. So, for her, physics was something, that yeah, you do it, but it is because it is done with maths, so that is the important bit. So, I had to learn it and start to love it.
So, I started with electronic engineering - I liked the waves, a lot of waves, interference. That is another magical thing happening in my field, so I like that very much. I started to study my major which is non-linear optics. Non-linear optics is another magical way of mixing colours of light together and getting other colours. That's the, that's the great thing. So, you have different colours of photons and you can, you can mix them and you can have other colours, but most of all, you can have your light doing interesting things by itself.
So this is what interested me a lot, because eventually, you study non-linear systems and when you have the nonlinearity, a physical system, somehow it starts to become alive because it does things that somehow it likes the most. If you work a bit with complexity with chaos you, or you will start seeing, so you try.
When you have a laser, you try to tell the laser what you want, but the laser will do what it likes better, eventually. So, I'd say sort of communication that you have with the system. This is what I, what I liked the most.
Great. Well, the next question is a brief summary of your research. You mentioned that you do, sorry, photonics was that what it's called?
So, in general, I obviously gave a little bit, but what's the main thing? So one of the big questions: when you introduce this kind of research field, or basically physics field, it is what difference do you have from photonics and optics because people have been calling optics would have been calling it, optics things that ever basically right. So, optics is the science of light and so photonics is the science of light. So, what's the difference between the two? Basically, there is no difference, just that when we talk about photonics we focus on the fact that the light behaves in the concise way with photons and when you can interact with the photons, you can do many things. So, photonics, somehow, it's the science is still physics but it covers everything that works with photons. So, you can, you can go very well in the infrared, the mid deep infrared, the THz down, down, down with your photons up to microwaves because they are still photons.
And then you can go up, up, up, up in frequency. So, everything is more or less the same type of science. It is not because the world doesn't like to react the same way to microwave and optical photons. But that is that is another story that is how the theme is born.
The other things that I was saying before, like working and working with linear optics non-linearity is, basically, the way in which the things that somehow, as I was saying before, are made, are made alive, right? So, we are as human beings a very, very good example of
non-linear systems. So, we grow.
Let's say all the properties of a, for instance, of our brains are obtained because you have the interaction of many, many different things for many neurons together; they interact together non-linearly and they create new things. From our thoughts to a feeling that we have in that, in our body. And the interesting thing is that when you add non-linearity to photons and to waves, they start to behave somehow in a similar way.
That's the interesting bit. There is a whole bunch of science that is focused on a particular kind of non-linear system. It's called non-linear dissipative system. And, that is a sort of research, is a Nobel prize in chemistry that he invented this stuff and one of the, somehow, targets of this field that is to fight, to create the, to understand physics, biology, and all the, all the science that we have around under a similar kind of, similar kind of light. So, the interesting thing of a non-linear dissipative system is the system is non-linear things interact together, and then the system is dissipative.
So, it doesn't have, so it needs energy to live and release energies and eventually dies. But in this process, you have the creation of life, the creation of many things. And, also you have the interesting behaviour of things that somehow organise themselves. So, in other important things, this kind of field is called the self-organisation of the element, so they can be, as I would say, the neuron food for your thoughts, but can be the waves that are in a laser.
So, the interesting thing for myself to all make up is to try to understand how the waves that in a laser somehow behave, so how they compose themselves and how they can do something useful for people.
So, one useful thing that I'm doing is to create lasers for the route for optical atomic clocks. But now we are jumping on another thing, Jessica, don't know if you can take a break. Shall I, shall I present some, some slides at this point?
That'd be wonderful, thank you.
So, now let's go into completely different things, because for now, I've been talking about light and things and talking to a laser to convince it to, to do what you want. So, now what is the thing that I would like to do with my laser? Let's see it here. So, this is an atomic clock. If you see this figure here - that is an atomic clock, so let's go, let's start from back.
So, this is how a clock works. So, in a normal clock, whatever clock is done by very important fact, that is, that is a reference. So, if you have a pendulum, you can have your, your reference. Usually, it's something that oscillates, usually a small, a small frequency there is low frequency, but then, you can use it to do what you can use it to count the time.
So, there are two main important parts in the clock. Something that oscillates that gives you this reference of time, and then you have something that allows you to count it. The interesting thing of an atomic clock is that you have usually this reference that is done by a very precise optic-atomic reference in the standard of time that we have right now. The reference is done with a caesium clock, so you have an oscillation many, many digits that there were 1.3 now, but it's on the order of nine-90 years. So, more or less, and then you can count with whatever it is, whatever electronics you want.
You can count this oscillation. To get an accuracy that, at the moment, is 10-13. So, why it is interesting to do clocks. So, it is interesting to do atomic clocks because we can do many things. So, one thing that we can do is to find our way with GPS.
So, this is something probably you have seen, that you have lots of experience with that. So, this accuracy of time is important for navigation. At the moment we are using all the synchronisation in the, with this atomic clocks that are sparse in the sky. And we use that, we use the signals.
Now, it would be good, if possible, to have it in something that you could take with you for whatever report, what reason, but we have a - that is a, that was an interesting study about the dependencies of all our life from time and upon the fact that you can go down with Pokémon Go and all the, and all the games I think people that are acting here. I think your clock and your GPS signal with that very, very interesting way. Or cheating, cheating in Pokémon Go, but the other interests, the other important thing is that these signals, apart from being used for you to find your way home, that is a very important thing, or to play with Pokémon Go is used for many, many things. Starting from the transmission of our electricity, the logistics chain, emergency, utilities, so all most important communication. All these things are synchronised with time. So, we are honourable to the GPS. And to decipher, and then we're vulnerable to lose the signal for the GPS; and many of these applications would pretty much work better if having a local time that they could control.
Now, the problem that we have right now is that to have the accuracy that we need for all these applications, you need a very complicated clock. So, what you would like to do now, I will jump over the story of what we have to do in that, in the future, what you would like to do is to put your GPS in a pocket.
So, the good thing that we have right now is that there are many, many, many people that know how to make atomic sensors in general, small enough to be brought around, so it is the moment to start to build up , something that feels nice and portable, to do the best clock that you can think about instead of using the microwave references that I was showing you before. You could think about using an optical reference. Why do you want to make, use of an optical reference? You want to lock to your reference because optics go so much faster than microwave. So, your resonance, if you remember the things from, from lab one, when you push it to very, very high frequencies, they are much more accurate with less effort.
So, the reference that you have in the optical machine is much more accurate than the one that you have in the microwave. What is the problem? The problem is that this reference here will oscillate at 200 THz. Now, how do you count 200 THz? You don't follow a frequency like that, so you need something that is a reduction gear, so if you think about the, the gears of mechanical gears, you have something that oscillates very fast.
You need to have, instead, this sort of wheel that slows down this, this oscillation and allows you to count it. So, the very clever way that you can do this is to use a pulse laser. And then we finally come to my laser here, to use a pulse laser. Now, that is, we're going to pulse. This pulse laser is not the simple pulse laser, is a laser produces pulses that are exactly in sync with this frequency, as you can see here.
And so it's a very difficult thing to do, and then you can count this light flashing on and off, at a much lower frequency, you know, you can use it for your clock. The idea of this comb, of this type of laser, it came through - sorry it I'm having a bit of a problem with the slides.
So, the idea of this came from John Hall and Theodor Hänsch and we liked that idea. We can have clocks with an accuracy of 10-18. So, with this, we can read a lot, a lot, a lot of things. So, that's just a little bit of an idea of where we would like to go and what you can do. So, you can do with this accuracy, you can do time keeping a GPS receiver, and the more accurate you are, the more things you can, you can actually do, but you need to make to have your system also a little bit small.
So, the interesting thing that we do in Sussex, let me do a little bit more forward, is that we have the capability of doing very accurate references, thanks to the work of Matthias Keller. And he has all the expertise to do this super accurate reference super small.
You see, this is a very something small like that. And then we do, when we go at work, I believe that is creating this, that this pulse reference here and to have all this oscillation. So, to have this ability of locking your frequency to your pulses is you need a very, very, very very, very, very broad spectrum.
So, if you look at these pulses those are in time, but if we imagine to pass it through a prism, then all the frequency will separate and you will get the spectrum that looks something like that. So, we've got a number of different colours that are all equally spaced. That's why we call it a comb. We call it a comb of light because these lines are all equally spaced.
And if we make it, so the ability of the difficulty of this system is to make all these lines very narrow and very spaced of all the same, the same amount, because otherwise we don't get any, any metrological activity. We do many things with it, this is just the idea because we can use molecular spectroscopy.
There are people that are capable of measuring the molecules in your breath and tell if you are sick or not with, with this type of spectroscopy, because it's very accurate. So really, a lot of possibilities. Right now, your comb looks something like that. What we want to do is put in a small chip, and I have taken the chip with me today because to show it to you all now.
You see written here. What you see at the moment, is a chip like the one that you use it for electronics. But these little circuits instead of being a circuit for a transfer electrons of metal and things, our little circuit of glass wave guide, where you put the light inside.
So, with this little chip, what we managed to do is that we are able to confine a lot the light, because the light is very confined. We can increase the density. So - just to show you - how do we get the light inside these chips. So, those are optic fibres you see here – okay, that's the little flag - you open it and from this little hole, you attach it to your optical fibre. And this is exactly the thing that we, that we use for the internet. So, all the cables that brings the internet are exactly like those. So, you have your light here coming here and going to the chip.
And then the magic that this coming here, that this happening, is that all the photons start to mix up together and we get this very precise set of equally spaced photons, because the photons are equally spaced in frequency, because the photons can be interacted with a lot, with a lot of energy.
And so, to give you an idea of the work we're doing, let me go again to my slides. So, you see here, that is the experiment that we have with the bits and pieces that we have in the lab. So, we are happy with this. We are happy that we did something very small.
It's a sort of box like that; the chip is inside this box. You see the chip here. That is what I showed you before. You see all the little fibres coming around, and then here happens what we call the magic. You see all this very nice, equally spaced lines that you see here. So, that is that, that is the comb, but, and all the comb is generated inside this ring of glass.
So, what does it mean? Does it mean that if we do the things properly very soon, we can have this stuff on the chip of your mobile phone or electronics? And then maybe we go, we go there. Now, we need to wait for the references, for the atomic reference, to go and be small enough, but when this is done.
You have already all the bit of your clock that will allow you to count your frequency, plus with all this stuff you can do spectroscopy, molecular spectroscopy. As I, as I was saying before, and I think that, with these, I can always stop sharing, and I should have, somehow, wrapped up very quickly what I do.
That's, and why, why I'm doing it apart for the, for the life, for the, let's say, of how, for the fact that I do like the non-linear system in general, but they can be useful also for doing practical things.
Awesome. Thank you very much. Have you got any tips or advice for current and future graduates?
Yes, it's resilience, Jessica. Don't, don't, don't never, never, never give up.
So, all this, I would have liked to show you my experiments in real time, but as usual we are in the moment of trying a very difficult thing that we blew up everything. So, the experiments usually explodes or you have bits and pieces that break. And usually they break when you really need the results out.
So, that is just the experiment alive, but there's nothing that you can do with that. So, the first thing that it's, is to be resilient for many reasons, for how things can go. You can have a bad day in exams. You can have many things that go wrong. But, in general, the most important thing is just not give up, have your reaction.
People will eventually, from my experience, understand what you are doing and why, why this is important, if you stick with that, stick with it. So yeah, I would say this is the point.
Thank you very much. And then, as a little bonus, can you think of a happy moment that's happened in your career?
Oh, I mean, there are many, there are many. So, I have funny moments, funny moments, or weird moments.
So, I have done a couple of interviews that have been really bonded to my family, to my family lives. So, one very interesting experience that was to get an interview for a grant as you know the research is coming with money that we need to, we need to attract somehow.
And when I was doing this interviewing for the grant, I was eight months pregnant. So, I was huge. And that I had the committee all around me just as a support to do this, this person that I took 30 kilos. So, I take in 30 kilos in my last pregnancy. So, I was really, really, really a huge person with the belly and everything.
And I was drinking like crazy because I didn't have enough, enough breath to go to go home, to go on. So, I drank almost one litre of water during this, during a 20 minutes interview. It went well, so everyone, but yeah, so it was, it was a little bit of something like that.
And, yeah, so that's a, that's probably a funny thing to tell around. And the other important thing is that I think that gives a bit of perspective also to women in science. And everything, you can do it, you can do it eight months pregnant. You can do it when you have, when you have little kids.
Because after this interview, I have done another grant interview when I went there with my, with my little one that just left to his father in front of the door before, before the interview, because he was very little and I was still, feeding him with maternal milk. So, I had to stay with, even the nights, like I couldn't travel properly. And I've done all this, but it comes somehow naturally.
So, they, so your family, your family life, your, your extended life, can, can work well with, with a career in science.
Thank you so much. Thank you for your time. It's been lovely talking to you.
Thanks, Jessica. Also, I've been loving to talk to you too. Thank you very much for the opportunity.
Sussex Loves Quantum - tour of the labs
- Video transcript
Thank you very much. Good morning everyone and welcome to the Sussex loves Quantum session this morning. And thank you KTN, for setting up this event. I'm sure it's been very difficult on all ends to deal with the circumstances, but it's great to have this wonderful program together this morning and, actually, throughout the day, we represent here the wide range of activities at the University of Sussex.
My name is Peter Kruger. I am in charge of the Sussex program for quantum research, which is encompassing all the different activities, not only in quantum physics, but also in enabling disciplines, such as engineering, all the way to, to schools of medicine, psychology, and life sciences applying the quantum technologies that we develop in our lab.
So, what we thought to do today is take you for a tour of our labs. And you'll see, in this session, all sorts of different ideas ranging from onsets of theoretical concepts, to actual technology developments and descriptions of our applications from small chip scale sensor devices, all the way up to large efforts in making the world's first real quantum computer.
So, we believe that it's important to integrate all these disciplines, but we also think it's important, and we're very happy and pleased to be part of national international networks, for example. And we are part of two quantum hubs. One is the quantum computing hub and the other one is for sensors and timing, which also happened to be a part of, and, you could say, I see the wide variety of activities there.
That all represented in various virtual booths throughout the day, as well from underpinning technologies all the way to the applications in geophysics timing, magnetometry for healthcare and navigation. And you see here the times, briefly, but we also believe in integrating industry.
And, of course, this is very relevant for the showcase today. And we're just launching a Sussex Quantum Partners program. You'll hear more about it. And please do ask us questions about it, and we'll have a big launch event next spring in March. But just before we start with the labs, I just wanted to encourage you to ask questions in the chat throughout this session, so that at the end we'll have time to answer some of them.
And you can ask any of us also in our virtual stands and download material of our various groups represented here. So, let me start with, with our cold atoms lab and Shobita here.
I'm a PhD student here and part of our research here is miniaturisation. So, to make a cold atom cloud inside the vacuum chamber, like this one, we need a lot of optics. I'll just show you our optics table here, and it goes further on that way. So that's quite a lot of optics for fine tuning, the lasers that go into, shine into the chamber so that we can cool our atoms.
And we also need these big coils, and also wires inside of the chamber, so that we can trap our atoms. So, one of the things we want to do is miniaturisation for commercialisation. So, the vacuum chamber, we can actually bring to some - switch to the other camera – so, this is 3D-printed vacuum chamber; it's a lot more compact.
And the coils and some of the laser fine tuning can actually be brought down to something around this size. And then, once we've got our atoms there, our cold atoms, we can actually use them for magnetic microscopy. So, one technology that's being developed, a touch screen technology that's being developed is nanowires. Hold on, if I can pick up the sample - nano wires with nano currents, picocurrents running through it. And, see that, on this is transparent nano wires. And what we can actually do is bring a sample like this very close to the atoms in the chamber. This would be a PCB that we put in the chamber and then, by imaging the atoms, we can actually get a current map of that sample. So now, I'm going to hand you back over to Peter, who's going to tell us more about quantum sensors.
Let me approach in a socially distanced way. We also have even more - let's get in frame here - probably closer to market, sensor devices, and then, based on something that I have in this little box here. I don't know if we can see that. Yeah, here, these are - if I can get closer to this [the camera]. These are little cells of warm atoms now, so we don't talk about cold atoms anymore, and we can mass produce them here. This is just a wafer scale manufacturing of vapour cells. In this case, they're Rubidium atoms and we can use them to integrate lasers and other devices and make, make sensors. That then fit into this kind of contraption here. This is a three dimensional, 3D-printed housing of a magnetometer that we can then use for applications, such as placing these sensors near my head, for example, they can measure brain currents and that can go into medical diagnostics or completely different applications.
I would love people to ask us questions about later, which is this kind of a device, which is an electric vehicle battery from a Nissan Leaf car, actually. And we can, again, place these sensors nearby and then we can have functional imaging of the electric currents, who are flowing in these batteries and learn about current flow there.
Just, as I have used up my time already, I will now pass on to the next lab. And that will be a photonics lab where Alessia will tell us about their work in frequency columns used for, for timing. Thank you. And Alessia please take the screen.
Okay. So, hello everybody and welcome to the emergent photonics lab. My name is Alessia Pasquazi; I direct the ultrafast photonics facility. So, why our lab is called emergent photonics. Photonics means that we work with light and that we use the emergent properties of complex systems. Basically, we want to, have the light to organise itself to do many useful things.
And one of the useful things that I'm going to show you today is how to do the counter of an optical atomic clock. So, atomic clocks, like every clock, have a counter and a reference, you can imagine that, a pendulum clock with your reference. And then the clockwork with lancets going around.
You will see after me, in the laboratory downstairs, the work of Mathias Keller - working on doing references for optic atomic clock. In our lab, instead, we are doing the counter of data in the room and fibre that you don't see over there. We can send him the signal downstairs. So, how do you count the frequency of light that is superfast? You use another laser and you count the pulses of this laser.
But this needs to be a very special laser with a spectrum that you use, something like that. So, it's called the comb because it's done from a series of equally spaced frequencies. And if you want to buy one, then it's one of these. This is how the commercial combs look. It's a big, it's a big system.
This is an extremely accurate comb from Menlo Systems. What we would like to do here is that it's thanks to the great ability of light to do things by itself, to go find everything in this, little chip like this, if you see it. So, this is an integrated chip and you see on the chip little, little circle of light.
What we do is that we confine the light very much within these, that optical screens with optical micro cavities and have the light itself interact and produce this cascade of system.
I want to show you the experiment planning. So, this is what you see in that, this is a running experiment at the moment, and with this other camera I can give you a sneak peek from my system. Here we go - now you see here. So, this is how the system looks like in this box. We have the microchip, that is thermalised. And then we have some bits and pieces. So, this is a standard optical amplifier, something that you can buy directly off the shelf, but we've done some simple optics that at this point we use to test that and end the path of our cavity, but eventually what we can have is a box more or less like that.
Thank you Alessia, next we have Mitchell, telling us about quantum computing.
Hello? Can everyone hear me okay? I'm Mitch. I'm here in the ion quantum technologies lab here at Sussex. So, you've seen some optical systems and tables. That's what I'm doing in front of here. So, what we are concerned with doing here is, is building quantum computers, but particularly we're focused on scalability.
One of the biggest challenges with quantum computing today is the ability to actually scale these things up to arbitrarily large sizes or, or sizes where you have a number of qubits, which are useful for doing useful problems. So, we have several experiments in here and they are all focused on different aspects of proof of principle experiments in order to try to realise a scalable approach to this. So, we're doing this with trapped ions, so we ionise atoms, and then we trap them using electric fields in the vacuum system. You can see them behind me We’re using laser beams to trap these, and as you can see, we have this large optical set-up to do that.
One of the differences with what we're doing in order to try to realise the scalable approach is, one of the limitations with using lasers to actually alter the point and states and control the cubits is that you need roughly a pair of laser beams for every ion you have, and your every ion you have is, is one qubit in your computer.
Then, you know, if you want to have a hundred thousand qubits, then you need roughly 200,000 lasers; and you can see how unwieldy and difficult and not very scalable that is just with two or three lasers that we have here for just doing the factory part. So, what we're doing is trying to implement this with a long wavelength radiation, or we are implementing this with long wavelength radiation.
So, we’re using microwave technology, which is again, old technology, and we can have an antenna inside there and just by having a large magnetic field gradient, which is across our array of qubits, and applying global radiation fields from microwaves, we can actually alter the quantum states of, and individually address those qubits just based on their relative positions in the magnetic field.
So, and, so that, that is the big picture. We also have some experiments here working on showing how you could, essentially, in order to actually get these things to interact with each other, these ions, they have to be able to move around in this very large array. If you want to build this in a modular way, you need to have a way of moving ions from one ion trap to another.
So, we have an experiment which is working on showing how, how you could essentially shuffle one ion from one ion trap onto another. So, essentially, it's always trying to move towards a modular way of building a quantum computer, and really, scalability is our middle name here. We also have our own stand at ten to three. So, if you want to ask any more questions do come along to that. Thank you very much.
Okay, so, thank you, Mitchell. It's good to say that there are these other stands and people can ask questions there and also please do use the chat, as some people have started to do, to field questions now and we will answer them at the end of the session. Now we move on for a short break from the labs to Barry Garraway, who does theoretical work and conceptual work, which is extremely important for us as well, and Barry will tell us some about his activity now.
Hi there, so hello everyone. So, in my case, no lab to show you, just a bookshelf and a note pad, writing paper, and computers, and things. But, as Peter was just saying, theoretical work has its place also in quantum technology. So, I'm one of a couple of theoretical groups here at Sussex, both of which are very keen on quantum things.
And in terms of quantum technology, the sort of things that we're working on, at least, sorry I'm working on, are cold atoms and atom chips in particular.
Why cold atoms? Well, cold atoms can link to matter waves. Matter waves can be highly sensitive things for looking at, sensing, for example.
And why atom chips? Well, atom chips can lead to miniaturisation, combined with ultra-small vacuum chambers, which can be on centimetre scales, combined with optical fibres and miniaturised laser systems, and so on, you can hope to make a highly compact sensor or other quantum device of some kind, and the specific things we are working on, well we've been working on rotation, sensing using matter wave guides.
We've been working on quantum information processing, not with ions, as you've been hearing about, but on the theoretical schemes for quantum information processing with atom chips, and neutral atoms stored within lattices, and we're working on all the things that try to destroy this effort on decoherence processes and in particular, in the quantum technology framework, on noise.
Noise from vibration and noise from electromagnetic fields and what these do to a matter-wave systems, as well as all that kind of work. There's fundamental quantum research going on as well. So, we're working on, for example, a bubble trap systems matter waves and shell potentials and bubbles that are also being tested on the international space station right now as we speak.
So, that's the range of the sort of quantum work that's going on in my theory group. I just want to finish by mentioning that I'm also editor of the Institute of Physics eBook, publishing a series in quantum technology. So, we've just started up and we're looking for authors who are interested in publishing eBooks with the advantages of eBooks. They can be a little bit more interactive; you can have 3D models, and this is quantum technology, so I think there's potential here to have authors of eBooks, both from the academic side and potentially from the commercial side, maybe with a story to tell about, you know, the route and pathway that goes to commercialisation of quantum technology.
And with that little plug, I think I will finish there. Thank you.
Great. Thank you, Barry. Next up is Manoj, talking about quantum materials.
Hello, everyone. It is good to see you here and welcome to our materials science laboratory. I am Manoj Tripathi. I am a research fellow here working with the professor, Alan Dalton, and here in the University of the Sussex we, as, as we are doing the material science research, we are here running through three different laboratories. One laboratory is dedicated to the synthesis of the nanomaterials, which we are synthesising metallic nanoparticles, nanowires that Shobita has shown you in her presentation and 2D materials like graphene and other exotic, photosensitive materials like molybdenum sulphide and tungsten disulphide. So, through the liquid exfoliation techniques, we synthesise these materials, and the in secondary stage we try for the basic characterisation, like how their mechanical and electrical properties, and the third stage, which is where we bring those materials in our advanced sophisticated lab, where I am right now sitting.
Where there is a combination of these materials, we can make some exotic device performance, like a strain sensor, or optoelectronics for the optoelectronics and the strain foundings. So right now, behind me you are seeing a combination of two surface technique. One is a Raman spectroscopy and then there is an atomic force microscope. Right now behind me you can see a saucer, behind this here we shine this laser light and get the phononic information of these nanomaterial. Then this will go from the spectrometer, a grading colour behind that, and there is 4 steps where we get the information about the shining of the laser.
We have customised this part and bring it to our atomic force microscopy, basically the principle behind the atomic force. Microscope is like a gramophone; there is a stylus and on top of the rotating plate, and then you can see the sound, but here in our lab, we get the physical manifestation of the nano world.
So, it's the sensors that attach to the atomic force microscopy look like this. These are the cantilevers, but I cannot touch it, otherwise I can break it. So one is for the physical sensor and one is for electrical sensor, it depends on what type of sensor we are looking at, is coated with the metallic, the nanoparticle the entire sensor is conductive then we can get the conductive information like a scanning tunnelling microscopy. The electron is tunnel between this metallic sensor at the tip and you can get the atomic resolution images.
So, this is a very pivotal role to know the device performance and industries are very keen to know that. And that's why we are in collaboration with the company like a Goodyear to improve the tire performance of the increasing mechanical properties and the original resistance, and also like the bank of England to provide the information about the barcoding.
And recently, in a joint venture with Advanced Material Development here in Sussex we are able to file a patent of the strain sensor from graphene balls so by the combination of liquid, like aqueous and oil we are able to make a spherical ball that acts as a marker of its property. So that's all from my side and I'm happy for any questions.
Thank you, Manoj. I think it's, it's a very interesting area that connects nicely to the quantum technologies and many fronts. So, when you come back to a different type of quantum sensors, now using trapped electrons, and detecting microwaves with - Jonathan. are you ready to tell us from your lab?
Hi, I'm Jonathan from the Geonium chip group with José Verdu. We're primarily focused on trapped electrons in a planar penning trap. So a penning trap uses static electric and magnetic fields to trap charged particles. And as I said, we're focused on electrons. So, we've chosen the planar geometry, as we're focused on making small, chip-sized penning traps. A conventional penning trap is quite a large, sort of many centimetre scale to meter scale device. So, we've, shrunk our penning trap down to, I think, one and a half centimetres there. If you just see the electrodes there, I think, it's 14 millimetres across. So that's the electric partner. So, small penning traps do exist, but if they're all let down by the large magnetic field that's required because you need a magnetic field in the order of the Tesla, which is very strong.
So, that's typically a sort of metre scale, superconducting, solenoid magnet. So, we have also planarising the magnetic field and reducing its to, sort of, 20-centimetre square device with, this is the very first prototype. So, the mark two is going to be 50 millimetres across, which is, obviously, a significant reduction in size from the meter-scale devices around at the minute. And we've demonstrated half a Tesla with that prototype there, which, when extrapolated to the cyclotron frequency of electrons corresponds to 14 gigahertz. So the gigahertz regime is very useful for communications, for radar, for microwave imaging, and a trapped electron in a penning trap is one of the most, well, if not the most sensitive sensor for my microwaves.
And so, it's been demonstrated that you can actually detect individual photons entering and leaving the electron system as jumps in the energy. So, you can't get any more sensitive than one photon. Sorry, did I say electrons? Individual photons entering and leaving the system. So that really is the limit of the sensitivity.
The whole trap is contained within a cryogenic vacuum chamber, which again, very compact here. So, it's approximately, sort of, 60 millimetres cubed so that's very small there, and the whole system fits in this vacuum chamber behind me which is roughly a metre size. So that's a huge reduction in size.
So we have a lot of commercial interest in this, including Leonardo and DSTL. They're more interested in the long-range detection, but there's also commercial applications in microwave microscopy and near field applications for high-frequency chips and things like that.
And, the possibility of a quantum VNA, which doesn't exist at the minute, so that's quite interesting. Um, what did we get to? Yes, so there's the second commercial application of it is branching away from electrons. A penning trap is a general ion trap and can trap any charged particle. And so, it can be used as a mass spectrometer as well.
Okay, thank you, Jonathan. So, next is Mathias, talking about portable atomic clocks.
I forgot to unmute of course myself, as usual. I hope you hear me better now. So, I'm Mathias Keller, I'm the head of the ITC and research group here at Sussex and our quantum technology research is focused on our two projects.
One is to build a node, kind of, for large scale quantum computer. And the other one is going to develop a portable atomic clock.
That project is in collaboration with Alessia; you heard already from her. So, let me start with the atomic clock project. Of course, the aim of the project is to take a lab-based atomic clock and you see that I'm standing here in the high position laboratory of my group. And you see right behind me these huge optical tables and, of course, we need to have for providing all the laser light energy infrastructure that you need to operate an atomic clock. And the aim off the project then it is to put all of that into a small 19-inch rack module. So for you, right, and so that can be, we have to develop techniques like fibre integration, so that optical fibre is integrated in the trapping structure, model, to make the system much more compact, but also more robust. How such a trap looks like, so that we have for all students in see here -
Matthias can you be closer to your microphone? It's very hard to hear you.
Okay. Maybe better now. Okay, it's like a reporter now. So here, this is an ion trap structure with integrated fibre optics that's necessary in order to make the system robust and suitable for a fieldable device. In addition, as you see behind me, the optical tables are mainly to carry all the optics and that's the point to generate the laser light probe for these ion traps
and can reasonably be managed on it. Let me see if I can lift that and to take on one of these optical tables and put that into this, this box here. So, what you see in here is essentially all the lasers that are required to operate an ion trap.
So, in combination with the optical micro holder Alessia Pasquazi is developing in the lab that homes an atomic clock, which outperforms significantly any commercially available system.
The second part of the technology development project we are working on is to develop a large-scale quantum computer and to do that we build small modules that can take and hold up 10 to 20 ions.
And we integrate advanced photonic features in order to make, to interconnect very easily, kind of, with each other. So, in this way, we can actually have photonic interconnects between small scale models that allows you then to build large scalable for a quantum computer. I don't have any prototypes with me at the moment, but just to give you an idea of size of such a module, it's roughly the size of the thumbnail of my finger. So that's roughly the sizing of such a module. Thank you very much, and I hope to hear from you.
Thank you, Mathias. Yes, back to the theory desk, Jacob will tell us about what more quantum can do to enhance measurement.
Thanks Peter. And thanks everyone for joining us today. My name is Jacob Dunningham and I'm a theorist, which is why I'm sitting here in my office rather than in a fancy lab somewhere.
I'm interested really in quantum sensing and metrology, as are a number of our experimental groups. And I'm particularly interested in how we develop and refine sensors for use in the field. So, these are things such as gravimeters for underground mapping of infrastructure, inertial navigation devices, and so on.
And I guess we know that field-deployable sensors need to be really robust. They also need to have excellent size, weight, and power performance, and one way that we can go about achieving this is to make sure that we make the most efficient, possible use of the information that we have available. And the theory of quantum metrology tells us how we might do this.
There's a really useful tool called the quantum Fischer information, which essentially specifies the most amount of information that we can get out of a given quantum state. So, if you like, it's a kind of a benchmark, it's something for us to aim towards. And so, what we can do is we can compare what we actually achieve in experiments with this benchmark and see how well we're doing.
So, we've done this for quite a number of standard metrology schemes, where we think we're doing pretty well, but find that actually, quite a bit of information is wasted and we ought to be able to do a whole lot better. So, we're going back, as part of the team here at Sussex, to revisit these schemes and see how they can work a little bit harder to see how we can squeeze more information out of them.
And I guess a key driving motivation is that we do this with very simple modifications. So, we're going after the low-hanging fruit. Essentially, we want to take an existing device, a sensor or something that you might have, make a very small or simple change to it and see how we can improve its performance.
One example is a gravimeter, which is, essentially, an atom interferometer, where we measure the state of the atom at the output. And from that we can infer the local gravitational field. Well, we've shown that if you measure other things, such as, perhaps, the momentum or the position distribution of those atoms, you can get a lot more information.
And you can also start playing around with the design of the scheme itself. So, start changing the architecture of the interferometer by changing things like the different pulse sequences, or you can end up with things that are a little bit intuitive as far as design goes. But they're very effective and you can see, you can easily get factors of two or even much larger gains in sensitivity.
And, these, I guess, are very important, not just because of the sensitivity gain they give us, but they give us the opportunity to do things like reduce the baseline at the interferometer. And so, make these things smaller, and so improve the size, weight, and power performance, which is what we're really after.
We're working with some experimental groups, including groups of Sussex and the Compact Gravity Gradiometer group at Birmingham to try out these ideas, to test them in the lab. Hopefully, eventually test them in the field. We're also exploring the idea of using these concepts to improve the robustness of systems. And the way this works is that any signal that we have will contain information on systematics.
So, if our sensor is on a moving platform, we're going to have information in the signal about that. And we're looking at algorithms for analysing and correcting for this. So, instead of treating it as a nuisance and a noise to be got rid of, we're using it as something useful that machine learning can help us analyse and correct.
So really, I guess what we're doing here is, we're trying to get the most information we possibly can out of existing systems, making small modifications to them to make them perform better. These can be applied, not just to the examples I've talked about, but to sensors in general, and we're very keen to talk to anyone who is interested in discussing these ideas in more detail, and particularly how it could apply to systems or sensors that you have.
So, thank you very much.
Thank you, Jacob. Now going over to Marco, talking about looking through terahertz eyes.
Hello. I'm Marco Peccianti. And what you see here is fundamentally a terahertz microscope. The idea is that we are trying to make imaging system microscopy system.
So, a micro functionally, that works in terahertz wavelength. And now to make this story short, - it's very difficult to handle. It's very difficult to generate because you don't have natural sources. And also, it's very complicated to manipulate because if you don't have device, you are too fast for electronics and actually too slow for photonics, if you want energy, the photon energy is actually too slow, too low. So, the basic idea we actually explore it in, quite a, a quite popular mechanism in the normal quantum mechanics imaging, which is the use of correlated photons, partially correlated photons. And one specific feature of this type of microscope is actually that it’s extremely fast.
So, we are able to resolve 50 pentaseconds in time. And this is the way we can, fundamentally, extract the chemical information of material. So, you can make an image. You can actually understand what the material is made of. And to give an example, so we can make, this is actually the temporal image of a leaf.
So, if you see here now, we show you what this one, this leaf represent, and so we can reconstruct in time. So, we are launching a very brief terahertz pulse on this leaf. And what you see is fundamental that the leaf has features inside that waters, have all sorts of biopolymers compound and that we can discriminate where the water is.
If the leaf is dry and it works more or less like x-ray technology. But the main difference is that we can actually tell the composition of the material. And also, we can, we can penetrate many material without x-rays, of course, they are tend to be awful. So, we don't want to, and simultaneously we also design ultrathin terahertz emitters.
So, things that can be applied to other devices to functionalise them, to keep terahertz to other surfaces, other electronics. And those tend to be extremely thin. So, we need to be able to make any surface, even a teapot. If you want to be able to generate terahertz in order to make a chemical analysis, a composition of what is behind.
So, and, I think is my time is pretty much up and that's pretty much it. Thank you very much.
Thank you, Marco, and thank you everyone. For these fast tours through all the labs at Sussex, I hope I gave people a glimpse of what's going on here, but, and also an impression that there are really many different things. We summarise all of them in our Sussex program for quantum research. Someone asked the question in the chat, what that actually is.
It's a, it's an internal network that allows us to, to have activities across the board, linked to each other and linked to the, most importantly perhaps, to the application areas in schools at Sussex, but also to external stakeholders, such as industry and other universities, of course. And, again, I want to point you to the stands that we have here, and one on quantum computing, and one is the Sussex loves quantum stand, where you can also book one in one-to-one meetings with us throughout the day and also, download material where you can read about all the topics that you've heard about. In the Sussex program for research, we have a number of people who can, sort of centrally, answer questions.
Rebecca here, who has been helping to set this up and answer any questions that have to do with them. Right. You can say yourself, what, what kinds of questions you would like to answer?
Well, so we have got one-to-ones today that you can book to speak to all the experts. So please, do book in today - we're here all day. And we've got the Sussex Program for Quantum Research, as we've talked about, and the Sussex Quantum Partners that we're launching in March. Our business development manager is here this morning that you can talk to about that as well.
And I think, I believe Rebecca, you put in a central email. So, if someone wants to essentially ask questions, and doesn't quite know who to put to direct, which scientists to directly ask, they can ask the question in, to that email, also outside the event today. We've had a number of technical questions as well, in the chat, they've been answered throughout.
So, I don't think we need to mention them separately, especially as we we're coming to the end of this session. I'd just like to thank everyone for their participation and showing their labs. And hopefully, soon we'll invite people back to our campus to actually see them in person. We are always happy to have visitors virtually, or even better in person, and then we'll even give you a coffee when you come to see us. Thank you very much for attending.
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