Spatiotemporal plane wave expansion method for arbitrary space–time periodic photonic media
Jagang Park, Bumki Min
Abstract
We have derived a systematic method to calculate the photonic band structures and mode field profiles of arbitrary space-time periodic media by adopting the plane wave expansion method and extending to the space-time domain. We have applied the proposed method to a photonic crystal with time periodic permittivity, i.e., the Floquet photonic crystal, and showed that the method efficiently predicts driving-induced opening of frequency and momentum gaps and breaking of mirror symmetry in the photonic band structures. This method enables systematic investigation of various optical phenomena in space-time periodic media, such as nonreciprocal propagation of light, parametric processes, and photonic Floquet topological phases.