On the conservation of optical angular momentum at acoustogyration diffraction of light

Abstract

Abstract.A phenomenon of acoustogyration diffraction of light is analysed from the viewpoint of conservation of orbital angular momentum. It is shown that the availability of optical angular momentum in the diffracted optical beam can be necessarily inferred from the requirements of angular-momentum conservation law. As follows from our analysis, circularly polarised diffracted wave should bear a doubly charged vortex, while its wave front should reveal a singularity typical of scalar fields. The efficiency of the spin-to-orbit momentum conversion is governed by the efficiency of acoustogyration diffraction of light.

Single-photon entanglement at acousto-optic (acousto-gyration) diffraction

“…It is obvious that the effect given by so a small size can hardly be detectable in practice. Nevertheless, the acousto-gyration diffraction can reveal very interesting peculiarities [24]. In fact, this effect manifests itself as a diffraction of, e.g., a right-handed optical photon (i.e., a photon with the SAM equal to    ) at a longitudinal acoustic phonon with the zero total angular momentum.…”