Quantum light–matter theory

The group develops the theory of how light interacts with matter when both are confined and strongly coupled, with a particular focus on emitters coupled to one-dimensional photonic channels. In this waveguide QED regime, photons routed along a single mode mediate long-range interactions between atoms, qubits, or quantum dots, giving rise to collective effects that have no counterpart in free space. The aim is to understand, predict, and design these many-body photonic states analytically and numerically, bridging quantum optics, condensed-matter theory, and nanophotonics.

A central theme is the interplay of superradiance and subradiance: ensembles of emitters can radiate cooperatively in bright modes or trap excitations in long-lived dark, subradiant states that are promising for photon storage and quantum information. The group also studies systems whose parameters are modulated in time, where periodic or structured driving opens routes to nonreciprocal transport, photon frequency conversion, and synthetic gauge fields for light. Understanding these phenomena matters for building scalable quantum networks, robust photonic memories, and on-chip devices where single photons are generated, routed, and entangled on demand.