Spin Orbit interaction of light in graded Index medium

Abstract

ABSTRACT newlineThe angular momenta of light associated with polarization, phase newlinesingular helical wavefronts, and shifted trajectory of a beam are referred newlineto as spin angular momentum (SAM), intrinsic orbital angular momentum newline(IOAM) and extrinsic orbital angular momentum (EOAM) respectivley. newlineThe mutual interaction and influence of SAM, IOAM, and EOAM of light newlinein a variety of physical configurations such as reflection, refraction, or newlinepropagation through an inhomogeneous or an anisotropic or a bi-axial newlinemedia leads to spin-orbit (SO) and orbit-orbit (OO) interaction (I) of light. newlineIn this thesis, we investigate the spin-orbit and orbit-orbit interaction of newlinelight in an inhomogeneous and weakly anisotropic (GRIN rod) medium newlineunder on-axis and off-axis symmetry considerations with Rytov- newlineVladimirskii-Berry (RVB) phase as an underlying mechanism. newlineInitially, the SOI and OOI due to on-axis (symmetric) propagation of newlinecircularly polarized (CP) Gaussian and linearly polarized optical vortex newline(OV) beam, resulting in spin to orbit AM conversion (SOC) and newlinereciprocal SOC are investigated. Further, the off-axis (asymmetric) newlinepropagation of vertically polarized Gaussian beam leads to different newlinephase gradients for right and left CP resulting in spin-Hall effect (SHE) newlineand Rytov-Vladimirskii-Berry phase accumulation, which exhibits a newlinenon-linear behaviour due to weak anisotropy of GRIN rod. Likewise, the newlineoff-axis propagation of linearly polarized optical vortex and zero OAM newlineHG beams are studied, which resulted in orbital-Hall effect (OHE) and newlineorbital-Berry phase (OBP) accumulation respectively. newlineAdditionally, mutual interactions of three AM of light are studied for newlinedifferent input launch positions through the GRIN rod system. The onaxis newlineand off-axis propagation of CP optical vortex (OV) resulted in newlineaddition and subtraction of net topological charge in orthogonal CP newlineprojection. The SHE under the influence of OV beam is investigated newlinewhich exhibits an asymmetric behaviour as a function of input launch newlineposition due to contributions from the OHE of li