Optically controlled fiber interconnection with photorefractive KNbO3

Abstract

Optically addressable fiber interconnects can be realized by using light deflection from photoinduced gratings. Such devices using isotropic Bragg diffraction have been proposed e.g. by Pauliat et al.1. Taking advantage of the anisotropic Bragg diffraction technique2,3 we demonstrate an all optical monomode fiber coupler with photorefractive KNbO3 crystals. KNbO3 is a very sensitive photorefractive material with large electro-optic coefficients 4: r42=380 pm/V and r51=105 pm/V. The anisotropic Bragg diffraction takes full advantage of these non-diagonal elements of the electro-optic tensor. With this method a beam deflector in a non-critical configuration has been built5 and investigated.