Theory Seminar: Quantum optical impurity models in interacting waveguide QED

Adrian Misselwitz
TUM
OQS Seminar, at the Theory Seminar Room
Friday, October 02, 14:30 CET 

We consider the effect of interaction in waveguide QED systems, consisting of photons localizing around atomic impurities in coupled cavity arrays while interacting via engineered local Kerr nonlinearities. Such a setup can occur naturally in analogue quantum simulators such as circuit QED lattices and ultracold atomic systems and leads to a scenario of competing interactions between the attractive Jaynes-Cummings-mediated binding and the intrinsic photon-photon repulsion. We analyze the resulting formation of few-photon bound states and determine the resulting many-body ground state for large periodic arrays of impurities, finding a rich phase diagram featuring Mott-like insulator states separated by superfluid phases.