Paraxial propagation in amorphous optical media with screw dislocation

Abstract

We study paraxial beam propagation parallel to the screw axis of a dislocated amorphous medium that is optically weakly inhomogeneous and isotropic. The effect of the screw dislocation on the beam's orbital angular momentum is shown to change the optical vortex strength, rendering vortex annihilation or generation possible. Furthermore, the dislocation is shown to induce a weak biaxial anisotropy in the medium due to the elasto-optic effect, which changes the beam's spin angular momentum as well as causing precession of the polarization. We derive the equations of motion of the beam and demonstrate the optical Hall effect in the dislocated medium. Its application with regard to determining the Burgers vector as well as the elasto-optic coefficients of the medium is explained.

Localized Excitation of Single Atom to a Rydberg State with Structured Laser Beam for Quantum Information

“…LG beams are characterized by three quantum numbers: (i) the wave number k, (ii) the intertwined helical wave fronts l (an integer number) of azimuthal phasedependent that features a screw dislocation, and (iii) the radial nodes p [48,50]. Each spiral photon in the LG beams carries lℏ of intrinsic orbital angular momentum (OAM) along the direction of propagation [51], which is arising from their nonuniform spatial intensity distribution.…”

Spin Hall effect of light in inhomogeneous axion field

“…The present work is motivated by the fact that inhomogeneity in propagation medium generally leads to spin transport effects [15][16][17][18][19][20][21]. We, thus, consider the effect of the spatial fluctuations of the axion field that have survived the inflation, on the spin (polarization) transport of light.…”

“…Spin transport of electromagnetic and transverse acoustical waves in weakly inhomogeneous media exhibits two principle features, which have been derived using the geometric optics approximation and its adaptations [15][16][17][18][19][20][21]. These features are (i) the rotation of the polarization plane (the Rytov rotation [23,24]) for linearly polarized waves, which is an example of the geometric Berry phase [25], and (ii) the spin Hall (or Magnus) effect for circularly polarized rays, according to which, rays of different polarization propagate along oppositely deflected directions [26,27].…”

The effect of Dirac phase on acoustic vortex in media with screw dislocation

“…The difference between this kind of beam and a plane wave is just an overall phase factor, e ilϕ . The angle ϕ is the polar angle in cylindrical coordinates for a beam with axis parallel to z and l is the optical vortex strength or the angular momentum that is carried by the helical beam [3,4]. When the helical beam interacts with a microscopic particle, the orbital angular momentum can be transferred to the particle and make it spin around the beam axis.…”