Chiral cavity quantum electrodynamics in a 3D microwave lattice coupled to a transmon qubit (Part 2)*

We have previously realized a chiral meta-material for microwave photons. We now describe our work combining a single transmon with this topological lattice, achieving, for the first time, a platform for chiral cavity quantum electrodynamics. We show strong coupling between the qubit and the topological lattice. Using the qubit we prepare arbitrary quantum states of the lattice edge modes and we can non-destructively measure their photon occupation. Finally, we describe a path towards coupling a transmon to each site of the lattice, enabling exploration of a Harper-Hubbard model which is anticipated to support fractional Chern insulating many-body phases.