Theory of interacting quantum many-body systems of atoms and photons

Cold atomic ensembles constitute a key platform for constructing quantum interfaces between light and matter that are the underpinning science for emerging quantum technologies from atomic clocks to quantum information processing. One of the success stories of nanophotonics in recent years has been artificially fabricated metasurfaces formed by thin nanostructured films of typically subwavelength-sized scatterers for the manipulation, detection, and control of light. Analogies of such metasurfaces utilizing cold atoms can be constructed by placing atoms in two-dimensional planar arrays, e.g., in optical lattices. A single layer of subwavelength-spaced atoms forms a quantum nanophotonic surface where scattered light mediates strong cooperative interactions. Tightly trapped atoms form a well-characterized medium where every atom has precisely the same resonance frequency and linewidth, all the light interacting with atoms is emitted back with no absorption, and even large arrays can in principle operate in a single-photon quantum limit.
The project is to develop theoretical tools for analysing such quantum many-body systems for atoms and light, and to solve them numerically. Cooperative interactions can then be harnessed to develop applications for quantum-optical manipulation of light. The supervision is conducted by meetings and discussions between the supervisor and student approximately every 1-2 weeks, or more frequently when special needs for those arise.