Ion quantum technology opportunities at Sussex
Quantum theory can have powerful applications due to the possibility of implementing new quantum technologies such as the quantum computer. While such a device could have very important commercial and national security applications due to the existence of quantum factoring algorithms, its existence would revolutionize modern day science by allowing true quantum simulations of systems that may be modelled classically only insufficiently due to an in-principle limitation of current computer technology. Recent developments in ion trapping technology show that it should be possible to build a quantum computer with trapped ions. At Sussex we pursue the quest to build a quantum computer, an effort that will be based in Sussex but include links to nanofabrication facilities, ion trapping groups and theorists around the world.
PhD in Quantum Technology and Nanoscience with Trapped Ions
A three-year PhD position is available in the Ion Quantum Technology Group in the Department of Physics & Astronomy at the University of Sussex. The position is part of the SEPnet South East Physics Network and in collaboration with the University of Surrey and the University of Southampton. It is in conjunction with an EPSRC funded £1.4M Leadership fellowship for the development of quantum technology with nanofabricated ion trap chips.
Research in novel quantum technologies will likely lead to step changing innovations which will affect many areas of modern sciences. Implementing such technologies with trapped ions quantum bits has been widely accepted as one of the most promising pathways. The aim of this studentship is to combine the scalability of condensed matter science and nano-fabrication with the unprecedented level of coherent control possible with trapped ions to produce a large scale architecture for quantum coherent control for large numbers of trapped ions. One of the main aims of the project is to develop ion chips that feature on-chip digital signal processing and incorporating approaches such as flip chip bonding in order to connectorize an ion chip with a digital signal processing chip creating hundreds of analogue voltages for all the ion chip electrodes, however, only requiring a few digital data inputs. The project will also focus on the surface science required to limit voltage fluctuations on the electrode surfaces within the ion chip electrode array. Such fluctuations limit how small such ion chips can be made and current studies show that some investigations into the appropriate surface science may be able create fabrication designs which are able to massively suppress such fluctuations. Furthermore, we will also carry out studies to implement basic cavities and fibre interconnects to the ion trap array for advanced ion quantum state detection capabilities. Based on what we have learnt so far in developing ion microchips, we also want to create microchips for large scale creation of coherent control of trapped ions on a chip. In order to do this we aim to implement microwave quantum gates on a chip.
You will learn all the experimental skills and theoretical background needed in this emerging field of science. Some of the skills you will acquire include nano-fabrication, lasers and optics, ultra-high vacuum techniques, quantum information science, electronics and many other skills. You will spend your first year primarily at Sussex where you will become an expert in ion trapping. Following that you will spend extended periods of time at the University of Surrey and Southampton carrying out microfabrication in state-of-the-art clean rooms. Once the first chips have been created, you will carry out quantum information experiments with trapped ions at Sussex. The position consists of current UK/EU fees and a yearly stipend of £ 13590 which can be supplemented by tutoring. In addition a research training support grant of £1,200 p.a. will be awarded for travel and conferences.
The city of Brighton & Hove has everything - sun, sea, brilliant clubs, great places to eat, fabulous shops, a truly cosmopolitan vibe and is located only 50min from central London. Located on the beach, Brighton boasts beautiful seaside views and beaches, boating, sports and beach activities. The South Downs provide breathtaking views, tranquil walks and plenty of opportunities for mountain biking, hiking or picnics.
Please contact Dr.Winfried Hensinger for more information.
Application deadline: 10 February 2012 (applications after this deadline may be considered if position is not filled).
Undergraduate research projects / Research placements
Laser cooling of ytterbium ions
Trapping single atoms is being described as one of the most demanding experiments in atomic physics. This project includes experimental work in trapping and cooling single ions towards the realization of an ion trap quantum computer. You will learn about laser cooling of ytterbium ions. Furthermore, you will study ways how to cool the ions to the quantum mechanical ground state. This project includes both theoretical and experimental parts. You will learn how to align lasers onto the ion trap, operation of a laser locking scheme, and the handling of a complicated imaging system as well as studying the theoretical foundations of how to manipulate ions using lasers. Your work should leads towards the experimental realisation of ground state cooling with trapped ions.
Advanced ion chips
For large scale quantum computing to occur large scale ion trap arrays need to be designed that allow optimal storage, shuttling and entanglement operations to be performed. The arrays are constructed within an integrated microchip. In this project you will study how to add advanced features to ion chips such as digital signal processing, on-chip cavities, fibre connects along with on-chip resistors and capacitors. In addition, you will devise recipes for the application of microwaves on the chip and the implementation of magnetic field gradients. You will identify important issues in nanofabrication of ion traps and address such challenges with advances in condensed matter physics.
Exploring optimal ion trap geometries
At Sussex, we are actively researching optimal in trap geometries for the implementation of large scale ion trap chips. This project will investigate different ion trap geometries and model different ion trap junction types. The aim is to find optimal geometries for shuttling, storing and manipulating single ions. Shuttling of single atomic ions that are used as quantum bits for a quantum computer is a complicated process and we need to understand how single ions can be efficiently separated from another, turn corners and be decelerated using optimal geometries for this purpose. Electromagnetic field simulations will determine the ion trapping characteristics of different trap geometries. In this project you will research such optimal ion trap geometries and find scaling laws to understand such geometries in depth.
Entanglement creation and quantum simulators
Quantum technology, particularly quantum computing relies on the ability to entangle ions. Entanglement has been referred by Einstein as “spooky” and is one of the most counterintuitive predictions of quantum physics. In order to create ion entanglement here at Sussex optimal ion quantum gates must be identified and the ion trap experiment must be modified to allow for entanglement gates. This may involve some theory, programming and experimental work. You will also evaluate how to increase gate fidelities in order to reduce error rates within quantum computing operations.
Ion quantum technology
Open topic, anything that you would want to investigate which falls under the general heading of ion quantum technology.
Please contact Dr.Winfried Hensinger for more information. A number of scholarship schemes are available for students from the University of Sussex and its Sepnet partners (University of Kent, Queen Mary / University of London, Royal Holloway / University of London, University of Southampton, University of Surrey). Note that there is no financial support available for students who do not carry out their undergraduate program at the University of Sussex or any of the SEPnet partner universities
Postdoctoral opportunities
Ion trap quantum information science is a fastly growing field with many opportunities. We currently have an opening for a postdoctoral position. More details can be found here. If you are interested, please contact Dr.Winfried Hensinger for more information.