Quantum electrodynamics of time-varying gratings.

Gratings which are in apparent motion reveal some startling properties for classical radiation, especially for luminal gratings traveling at or around the speed of light. We show here that their quantum properties are even more remarkable, their effective refractive index modeling the Schwarzschild singularity which as we show generates spontaneous Hawking radiation in correlated photon pairs. Subjected to external radiation, luminal gratings provoke stimulated emission of photon pairs which we propose as a possible means of observing Hawking radiation in the laboratory.