Drive-enhanced Superradiance in Circuit QED

We recently analyzed theoretically how two-photon driving of a cavity could be used to exponentially enhance the light-matter coupling in a cavity QED system, allowing a weak coupling system to exhibit features of ultra-strong coupling [1]. Here, we extend this idea to a system where an ensemble of two-level systems couple weakly to a cavity. We discuss how the superradiant phase transition manifests itself in this system, and how it is sensitive to the structure of the input noise driving the cavity. We discuss potential implementations using superconducting circuits, where simple flux-pumping provides the necessary driving. Our scheme allows for a tuneable analog quantum simulation of the open-system Dicke model. [1] C. Leroux, L. C. G. Govia, and A. A. Clerk, arXiv:1709.09091.