Ion Quantum Technology at Sussex
Welcome to the web page of the Ion Quantum Technology group at the University of Sussex, Brighton, UK. The group is headed by Prof. Winfried Hensinger. Our aim is to develop new quantum technologies, in particular, the ion trap quantum computer. For this purpose our research focuses on applied experimental quantum information science and development of new scalable methods to build ion trap arrays and the next generation of large scale entanglement. We are in the process of constructing a quantum simulation engine and a large-scale trapped-ion quantum computer. Another research area is the development of quantum sensors. The group is part of the UK Quantum Technology Hub on Networked Quantum Technologies and the UK Quantum Technology Hub for Sensors and Metrology. The group is part of the Sussex Centre for Quantum Technologies.
More information about our research, grouped by different target groups, can be found in the Research Section. Here you can find videos, explanations, interviews with current students and other useful information.
The Frontier of Computing
Department of Energy
Researchers from the University of Sussex and Universal Quantum have demonstrated for the first time that quantum bits (qubits) can directly transfer between quantum computer microchips and demonstrated this with record-breaking speed and accuracy. This breakthrough resolves a major challenge in building quantum computers large and powerful enough to tackle complex problems that are of critical importance to society.
Professor Winfried Hensinger presented his personal journey spanning three continents and four countries, in a bid to achieve his goal of building a scalable quantum computer. He discussed the future of quantum computing and quantum technologies in academia and industry at the Careers in Quantum online event on 3 June 2021, organised by the University of Bristol Quantum Engineering Centre for Doctoral Training. You can watch the advice he gave here.
We are happy to announce a strategic partnership with full stack quantum computing company Universal Quantum. Universal Quantum is a spin-out from the Sussex Ion Quantum Technology group. This partnership will allow us to develop and construct practical quantum computers. More information can be found here.
He announced £94M investment for the second phase of UK’s Quantum Technology Hubs which includes funding for the development of microwave trapped ion quantum computing at Sussex
The University of Sussex’s Ion Quantum Technology Group, headed by Professor Winfried Hensinger, has been selected to participate in the European Quantum Technology Flagship initiative. (more…)
Professor Winfried Hensinger, Director of the SussexCentre for Quantum Technologies and Head of the Sussex Ion Quantum Technology Group appeared before the House of Commons’ Science and Technology Select Committee on 17 July, to give evidence as part of the Committee’s inquiry exploring the opportunities and challenges for new quantum technologies. (more…)
The University of Sussex won both gold and silver at the national HEIST Awards for education marketing in Manchester on Thursday 12 July.
As part of the British Science Fesival we exhibit a walk-in quantum computer model, 5-9 September, 11am until 3.30pm, on Sussex campus. Winfried Hensinger will also give a public lecture on Tuesday September 5th, 2017 14:30 A2, Asa Briggs Arts, University of Sussex campus. Click here for more information.
Winfried Hensinger was invited to present the US Department of Energy’s Cyber Distinguished Speaker Series lecture to explain quantum computing to US government officials. Click here to watch now
PhD student Anna Webb has won a University-wide competition explaining her PhD in just three minutes. A news article describing this achievement can be found here.
Four Phd positions in quantum technologies with trapped ions are availalable in the areas of: Microwave Quantum Computing and Simulation with Trapped Ions, Developing a trapped-ion quantum computer demonstrator device, Quantum technology for finance and other commercial applications, Quantum sensing with trapped ions. Info available here.
Winfried Hensinger will speak at the this year’s Cheltenham Science Festival on Friday June 5 – ‘Can we build a quantum computer?’.
Book author John Gribbin, Biolologist Laurence Pearl, PhD student Kim Lake and Winfried Hensinger give a short introduction to quantum computing for the Physics World special about 5 physics spin-offs that will change our lives.
Marcus Hughes passes his viva and is awarded the degree of Doctor of Philosophy.
Chris Reed is awarded the prize for the best BSc. project in the Department of Physics & Astronomy at Sussex.
Seb Weidt is awarded the EPSRC doctoral prize for his outstanding PhD work.
Come and explore Ion Quantum Technology research at Sussex using our new interactive display, located in the Pevensey 2 building right in front of the IQT lab.
James Siverns successfully defends his thesis on 12 January.
Robin Sterling successfully defends his thesis on 30 November.
James McLoughlin successfully defends his thesis on 25 October.
Dr Altaf Nizamani is awarded the degree of Doctor of Philosophy on 6 August.
James McLoughlin submits his doctoral thesis on 1 June.
James Siverns submits his doctoral thesis on 30 June.
The IQT group received a grant from the Sussex Enterprise Development Fund for another commercialisation project.
Altaf Nizamani successfully defends his thesis on 6 May.
Robin Sterling submits his doctoral thesis on 20 May.
Altaf Nizamani submits his doctoral thesis on 21 February.
The IQT group received a grant from the Sussex Enterprise Development Fund to commercialize a specialized laser.
Ben Jacques-Parr is the recipient of the departmental Pamela Rothwell prize for an outstanding BSc. research project.
Winfried Hensinger has been awarded an EPSRC Leadership Fellowship with full economic cost value of £1.4M for the development of quantum technology with nanofabricated ion trap chips. A postdoctoral position (up to 5 years) and a number of PhD scholarships are available. Please get in touch if you are interested.
Marcus Hughes is the recipient of the departmental prize for an outstanding Master of Physics research project.
Rajiv Ramasawmy is featured on the cover of the departmental prospectus featuring lasers in the mist (in our lab).
Jessica Grove-Smith is the co-recipient of the departmental prize for an outstanding Master of Physics research project.
First lasers are operating and the overhang for the optical table is completed.
Dan Brown, Nik Davies, Jack Friedlander, Jessica Grove-Smith, Ben Pruess, David Scrivener and Tim Short successfully complete their undergraduate research projects.
The optical table has arrived.
4 graduate students and 8 undergraduate research project students join the group.
Lab is nearly finished, equipment will be ordered soon.
Collaborative research at the University of Michigan
Arrival at Sussex
We show how one can make use of a wide range of quantum control methods to raise fidelities and robustness of two-qubit gates with trapped ions.
The paper was published on 27 September 2022 in Journal of Physics B: Atomic, Molecular and Optical Physics.
We present the demonstration of a quantum matter-link in which ion qubits are transferred between adjacent QC modules. Ion transport between adjacent modules is realised at a rate of 2424 1/s and with an ion-transfer fidelity in excess of 99.999993%. Furthermore, we show that the link does not measurably impact the phase coherence of the qubit. The realisation of the quantum matter-link demonstrates a novel mechanism for interconnecting quantum computing modules. This achieves a key milestone for the implementation of modular quantum computers capable of hosting millions of qubits. Published on 8 February in Nature Communications.
We have determined how a quantum computer could break the encryption of Bitcoin and simulate the FeMo-co molecule, a crucial molecule for Nitrogen fixation. We show that in certain situations, architectures with considerably slower code cycle times will still be able to reach desirable run times, provided enough physical qubits are available. Four years ago, we estimated that a trapped ion quantum computer would need a billion physical qubits to break RSA encryption equating to a size 100m2. With innovations across the board, the size of such a quantum computer would now just need to be 2.5m2.
The paper was published on 25 Jan 2022 in AVS Quantum Science.
We propose a new microwave gate which uses the intrinsic J-coupling of ions in a static magnetic gradient. The gate is virtually insensitive to common amplitude noise of the microwave fields and enables high fidelities despite qubit frequency fluctuations, while the J-coupling interaction’s inherent robustness to motional decoherence is retained. Errors far below the fault-tolerant threshold can be achieved at high initial temperatures, negating the requirement of sideband cooling below the Doppler temperature.
Microfabricated ion-trap devices offer a promising pathway towards scalable quantum computing. Addition of on-chip features, however, increases the power dissipated by components such as current-carrying wires and digital-to-analogue converters (DACs). Presented here is the development of a modular cooling system designed for use with multiple ion-trapping experiments simultaneously enabling efficient cooling to 70K while provide significant and scalable cooling power.
The cost of enabling connectivity in Noisy-Intermediate-Scale-Quantum devices is an important factor in determining computational power. A particular architecture for trapped-ion quantum computing relies on shuttling ions. An efficient ion routing algorithm has been created along with an appropriate error model, which can be used to estimate the achievable circuit depth and quantum volume as a function of experimental parameters.
Our paper has been published in Advanced Quantum Technologies 3, June 2020 Efficient Qubit routing for a globally connected trapped ion quantum computer
University of Sussex Research News press release, August 2020 Sussex study enables predicting computational power of early quantum computers
Ion trap microchips form the core of many quantum technologies, in particular, the trapped ion quantum computers. We provide an overview of state-of-the-art microfabrication techniques, as well as various considerations which motivate the choice of materials and processes. Finally, we discuss current efforts to include advanced, on-chip features into next generation ion traps. Our paper has been published in Nature Review Physics, June 2020.
Building a practical quantum computer with large numbers of qubits will require quantum gates that are robust in the presence of fluctuations in operational parameters. In addition, motional heating of trapped ions will lead to a reduced entangling gate fidelity. (more…)
We introduce a powerful technique to transform all existing two-level quantum control methods to new multi-level quantum control methods. We illustrate the technique by coherently mapping between two different qubit types with error well below the relevant fault-tolerant threshold, creating another important tool towards constructing a large scale quantum computer. (more…)
We unveil the first industrial blueprint on how to build a large-scale quantum computer. The work features a new invention permitting actual quantum bits to be transmitted between individual quantum computing modules in order to obtain a fully modular large-scale machine. The work is published in Science Advances. (more…)
We describe a new approach for trapped-ion quantum computing based on the application of global radiation fields and voltages applied to individual gate zones. Using this technique we demonstrate a two-qubit quantum gate producing a maximally entangled state with fidelity close to the fault-tolerant threshold. This quantum gate also constitutes a simple-to-implement tool for quantum metrology, sensing and simulation. (more…)
We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering.
Published in Physical Review Letters.
We propose a new quantum gate utilizing microwave radiation and dressed states that is highly robust to decoherence making it an attractive candidate for the implementation of high-fidelity microwave quantum logic. Published in the New Journal of Physics.
We have developed a new method to efficiently prepare dressed state qubits and qutrits, thereby significantly reducing the experimental complexity of gate operations with dressed-state qubits. Dressed states are well protected from noise making them ideal for use in many quantum technology applications. Published in Physical Review A and selected as ‘Editor’s Suggestion’.
We demonstrate spin-motion entanglement using longwave radiation. This is a critical step towards the experimental realisation of high-fidelity two-qubit gates using microwaves rather than laser radiation. Published in Physical Review A.
Demonstration of the first two-dimensional ion lattice integrated on a microchip. We realize a two-dimensional ion-trap lattice on a microchip using a new fabrication method that allows very-high voltages to be applied to the chip, enabling very deep ion traps. Published in Nature Communications.
Article on how to create optimal two-dimensional ion trap arrays for quantum simulation, published in New Journal of Physics (14 August 2012)
Article on the application of radio-frequency voltages to ion traps via helical resonators, published in Apl. Phys. B (17 January 2012).
Article on the principles and operation of microfabricated ion traps including material considerations, a guide to the appropriate fabrication design, details of different fabrication processes and a summary of previously realized structures, published in Contemp. Phys. (14 Sept. 2011).
Article on how to create optimal electrode configurations for separation and trap depth in surface ion traps, published in Applied Physics B (28 Nov. 2011)
Versatile ytterbium ion trap experiment for operation of scalable ion-trap chips with motional heating and transition-frequency measurements
Article on design and operation of an ytterbium ion trap experiment with a setup that can host advanced surface and multilayer ion trap chips. We make a heating rate measurement and provide transition frequency measurements more precise than previously published work, published in Phys. Rev. A (21 Jan. 2011)
Article on Dopper-free Yb spectroscopy of Yb using a fluorescence spot technique providing frequency measurements that differ from previous published work and allowing to determine the average velocity of atoms along an atomic beam, published in Phys. Rev. A (8 Oct. 2010)
Single ytterbium ions are trapped in an experimental setup particularly designed for the development of advanced ion trap chips. This setup allows for rapid turn-around time, optical access for all type of ion trap chips and up to 100 electric interconnects. The particular ion trap used features an ion – electrode distance of 300 microns and we observed an ion life time of more than 1 hour.
Article on the transport of ions in large scale multi-dimensional ion trap arrays is published in “Quantum Information & Computation”.
Measurement of motional decoherence scaling for an ion trap with moveable electrodes, demonstrated significant suppression of patch potential heating, demonstrated ion trap with 23 microns ion-electrode spacing in experiments at the University of Michigan published in Physical Review Letters.
First two-dimensional shuttling operations including corner-turning and swapping two ions inside a T-junction
Experiments carried out at the University of Michigan reporting first two-dimensional shuttling operations including corner-turning and swapping two ions inside a T-junction published in Applied Physics Letters.