Designing Out-of-Equilibrium Many-Body Quantum Systems

Huge amounts of data are routed through the internet and are being processed by our computers and mobile phones every second. Always being connected to the internet has transformed many aspects of our lives, from the way we do our shopping to how we meet friends. The demand for further improving our ability to process data is driven by ever more devices being connected to the internet and services being moved online to improve our quality of life.

The physical principles underlying our technology to store and process data are based on our understanding of out-of-equilibrium dynamics. Better control of this physics is crucial to further shrinking electronic devices and to address the major challenge of developing energy-efficient switching and communications links. Such further progress in information processing technologies is expected to heavily rely on quantum effects like superposition and entanglement in the near future.

In addition, as the fruits of the recently initiated National Quantum Technology Programme start to become available after 2020, it will be even more important to have the knowledge in place to be able to face the next generation of technological challenges, such as the scaling up of the newly developed quantum devices. How to exploit the advantages of these increasingly complex devices in the presence of noise and decoherence is intrinsically an issue of out-of-equilibrium many-body quantum physics. It is therefore crucial to put methods in place now that will underpin the design of out-of-equilibrium quantum systems.

Our vision is to explore, understand, and design out-of-equilibrium quantum dynamics that are relevant for such future communication and quantum technologies, using quantum simulators with ultracold atomic gases in optical potentials. Ultracold gases are a unique platform in that they offer controllability and versatility in the quantum regime that is currently unparalleled by any other quantum system. We will set up and investigate ultracold atom simulations to help planning and designing out-of-equilibrium many-body quantum dynamics similarly to how wind tunnels are utilized in aerodynamics.

This project will capitalise on these capabilities by exploring three broad aspects of out-of-equilibrium dynamics that are especially relevant for future technologies: (i) switching behaviour of driven quantum systems, which could also be used to design enhanced classical information processing devices; (ii) driven quantum systems as quantum-enhanced sensors; and (iii) engineering emergent phenomena in driven quantum systems. Our activity will bind together existing internationally leading researchers within the UK on a novel common project of high scientific interest and technological relevance. This provides a unique opportunity for the UK to adopt a world-leading position in the use of quantum simulators to explore out-of-equilibrium dynamics in quantum many-body systems.

The first impact of this work will be in the developing quantum technologies industry. The new understanding we generate of out-of-equilibrium dynamics will provide means towards a new generation of quantum-enhanced devices for measurement and sensing. It will also allow us to understand the further scaling up of existing devices, by accounting in new ways for decoherence and noise. This will have strong benefits on the end-users of these technologies, beginning with the National Network of Quantum Technology Hubs in this area, continuing with the National Physical Laboratory, and extending to wider industry. Our new platform for quantum simulation with these systems will provide design inputs for further future developments. We will similarly impact future generations of quantum technologies based on quantum simulation, and their possible applications in industry, through the benchmarking techniques we realise with out of equilibrium dynamics.

Our work will also help to deepen understanding of switching properties in electronic and opto-electronic systems. This could have long-term applications in a number of areas, including optimising energy consumption in computing and data centres. This will be of interest to a range of potential partners investigating new switching mechanisms and optical data transfer technologies for large data centres. This is important to large computing companies, and will connect to ongoing research in a number of existing programmes with industrial engagement, including the SU2P partnership between Stanford University and Scottish Universities.

Our further exploration of emergent properties in out-of-equilibrium dynamics is likely to generate scientific understanding that has a direct bearing on materials development. In particular, spectacular progress has recently been made in inducing superconductivity in quantum materials by optical driving, far above their usual critical temperature. By exploring the physical mechanisms leading to superconductivity using quantum simulators, we hope to understand basic design principles that later lead to advances in the control of these materials. At the same time, we will investigate the role of dissipation in quantum transport, helping us to understand fundamental limitations on energy dissipation in electronic devices.

Another important impact of this project will be in training highly-skilled researchers, especially RAs and aligned PhD students, in an interdisciplinary area. This training aspect is particularly important in light of the growing opportunities in industries related to quantum technologies.

The wider public will also benefit directly from a range of public engagement events that address the topics of our research and impact on the development of quantum technologies. Such activities will occur at both formal and informal levels with schools, science centres, museums, and other similar institutions, and include, e.g., lectures and presentations of quantum optics experiments. We are also planning to host public lectures, e.g. by inviting Nobel Laureates to speak on Quantum Physics or related topics to general audiences. This will help inform the public about the role of fundamental research in the pipeline for quantum technologies, and will help to inspire a next generation of scientists from a diverse range of backgrounds.