All-optical switching based on grating written photorefractive slab/fiber waveguide coupler

A slab/fiber geometry will be investigated for all-optical-switching. Here, the slab is a thin layer of polymer or crystal, showing a moderate photorefractive effect, attached to the core of optical fiber. The thickness of the slab is just enough to accommodate the refractive index change depth of the grating which is written externally via an intensity distribution of two coherent beam interference.