Photorefractive recording by a special mechanism in planar LiNbO_3 waveguides

Abstract
Recording of holographic gratings in z-cut LiNbO3 waveguides with extraordinarily (TM) polarized light is demonstrated. In this geometry, photovoltaic currents perpendicular to the guiding layer and the grating vector set up space-charge fields. The mechanism has no equivalent in bulk material.