Intracavity Bragg grating

Abstract

Bragg diffraction of a read beam is studied theoretically when the refractive-index grating is placed inside a Fabry–Perot cavity. Diffraction efficiency, angular selectivity, and signal-to-noise ratio are largely enhanced compared with those for the bare Bragg grating, which may permit the use of low-efficiency or short-length materials as well. The results are much better for an asymmetric cavity operated in reflection than for a symmetric cavity in transmission.