Artificial Electromagnetism

In 1982 Richard Feynman introduced the concept of a quantum emulator, as a possibility to circumvent the difficulty of simulating quantum physics with classical computers. His idea, based on the universality of quantum mechanics, was to use one controllable device to simulate other systems of interest. Nowadays Feynman's intuition is being implemented in various setups and among them, cold gases of neutral atoms play a central role. These gases indeed constitute remarkably flexible playgrounds. They can be formed of bosons, fermions, or mixtures of both. Their environment can be controlled using the potential created by laser light, with harmonic, periodic, quasi-periodic or disordered energy landscapes. Interactions between particles can be adjusted using scattering resonances. At first sight the only missing ingredient is the equivalent of orbital magnetism, which would allow for the simulation of phenomena such as the Quantum Hall effect. This proposal fills this gap.

We will study optically induced artificial electromagnetism and gauge fields in ultracold quantum gases. With artificial gauge fields we have a new tool at hand, and with a new tool one can do new things. The programme will investigate and stretch our understanding of matter and its constituents at the most fundamental level. It will be dealing with concepts ranging from the ultracold to the ultrahot; concepts from low temperature condensed matter physics and high energy physics with its description of interactions between elementary particles.

The artificial gauge potential is optically induced. It relies on the geometrical phase arising from the interplay between incident laser light and the atoms, or alternatively on laser assisted tunneling in optical lattices. The resulting gauge potential in these scenarios can be made strong, it can be made inhomogeneous, and it can have a multi dimensional matrix form. One can therefore access regimes which are not easily reached in conventional condensed matter systems and high energy physics.

In the proposal we will take the concept of quantum simulators to an entirely new level. We will theoretically investigate a number of key scenarios which will probe the innermost nature of matter and its fundamental interactions, with a clear aim to provide blueprints for the experimentalists to simulate models of quantum field theories and topological states of matter using ultracold atoms which are subject to artificial gauge fields. Three related sub-topics will capture the nature of the programme: (I) Spin-orbit coupled quantum gases, (II) Anyons in ultracold matter, and (III) Dynamical artificial gauge fields.

Knowledge. This research is purely curiosity driven. The concept of artificial electromagnetism gives us access to a new tool for controlling ultracold matter. It will enhance our understanding of matter at the most fundamental level. This is the main driving force behind the entire project, and is the area in which we envisage the biggest impact will be.

People. The research aims to enhance the pool of scientific talent in the UK. Researchers and PhD students related to the proposal, but also on a broader basis through the Scottish Universities Physics Alliance (SUPA), the Scottish Quantum Information Science network (QUISCO), and the Scottish Condensed Matter Doctoral Training Centre, will benefit from it.

Society. Matter, the control of it, and most importantly, the understanding of it, has undoubtedly shaped our civilisation at the most fundamental level. This project will probe and question our understanding of the various states of matter we know today. It will open up avenues for exploring new exotic meta materials with yet unknown properties. As such it has the potential to reshape the way we live our daily lives.

Economy. There is no short term economic impact of the current proposal. Long term economic impact, we can only speculate about. It is, however, not difficult to envisage a number of potential technological applications, such as the enigmatic fault tolerant quantum information processor, which would stem from improvements in our ability to understand, engineer and control quantum systems and the various states of matter. Well established technologies such as quantum metrology (e.g. atomic clocks) and superconductivity are examples of concepts which have already a commercial impact, and rely critically on our ability to control systems at the quantum level.