Floquet Proximity Effect

We introduce the concept of "Floquet proximity effect," in which the usual equilibrium proximity effect is modified by the presence of a strong periodic drive at the interface. We develop the general theory of Floquet proximity effect and obtain the Floquet mean field equations, which yield the frequency-dependent induced order parameter. To illustrate the effect, we consider a Dirac system such as the surface of a topological insulator in proximity to an s-wave superconductor. The Floquet proximity effect modifies and induces effective frequency-dependent pairing amplitudes in both systems. Thus, we provide an avenue to the theoretical and experimental study of dynamical superconducting pairing induced by Floquet proximity effect.