A quantum simulation platform of photon dynamics using multimode superconducting cavities

Three-dimensional superconducting microwave cavities can host multiple spatially overlapping photonic modes separated in the frequency domain. When a collection of such modes are coupled to another bosonic mode at a different location via a tunable coupler, they naturally implement a quantum simulation platform consisting of multiple bosons connected via a star geometry. Such an all-to-one coupling geometry allows the global system behavior to be controlled via the central mode alone.

Leveraging the long lifetime and versatile control offered by such a device, we study its use as a quantum simulation platform for multimode photon dynamics. We present ways of initializing the system and reading out the final state, as well as using trotterized pulses to simulate the time evolution of a continuous-wave Hamiltonian. We discuss methods of tuning the parameters of the simulation including on-site disorder, coupling coefficients and the nonlinearity of the central mode. The performance of such a system is characterized using a simple quantum walk experiment. Finally, we comment on the prospects of using this system to study phenomena such as many-body thermalization.