Acoustic polarization singularities arising under torsion and orbital angular momentum exchange at the backward collinear acousto-optic diffraction: a case of crystals with point symmetry 3m

Acousto-optic interaction of the optical and acoustic singular beams

“…The acousto-elastic effect induced by torsion stresses in LiNbO 3 crystals 15,16 has been considered. It is shown that mechanical torsion can give rise to the acoustic singularity of the eigenvectors of the Christoffel tensor, and a torsioninduced 'acoustic birefringence' is conically distributed in space, with an elliptical cross-section.…”