The precession of vortex-beams in a rotating uniaxial crystal

TL;DR

This paper investigates the precession behavior of optical vortices in a nearly perpendicular propagation through a rotating uniaxial crystal, combining theoretical analysis and experimental validation, and introduces a device for controlling vortex trajectories.

Contribution

It provides a new theoretical and experimental study of vortex precession in rotating uniaxial crystals and proposes a novel optical reducer for vortex trajectory control.

Findings

Vortex precession depends on the differential rotation of beam and crystal axes.

Experimental results confirm the theoretical predictions of vortex behavior.

The optical reducer effectively controls the vortex trajectory shape.

Abstract

We consider theoretically and experimentally the precession of the optical vortex in a singular beam propagating nearly perpendicular to the crystal optical axis, the beam and the crystal axis rotating with different angular velocities. The precession is a result of different scales along the major axes in a uniaxial crystal. Also we analyze the properties of the optical reducer consisting of two rotating crystals and a wave retarder between them permitting us to control the form of the vortex trajectory.