Self-diffraction of recording beams in a 90° photorefractive crystal geometry

In this paper, we study self-diffraction of differently polarized waves in the geometry when the reference and object beams propagate the orthogonal directions. It was found that this configuration of photorefractive wave mixing supports the linear phase-to-intensity transformation when the object beam is unpolarized. It occurs because the horizontally polarized component does not interfere with the reference beam in the 90deg-geometry but the diffraction of this component from the hologram recorded by the vertically polarized component does not satisfy the quadrature condition.