Depolarization of Vector Light Beams on Propagation in Free Space

Abstract

Nonparaxial propagation of the vector vortex light beams in free space was investigated theoretically. Propagation-induced polarization changes in vector light beams with different spatial intensity distributions were analyzed. It is shown that the hybrid vector Bessel modes with polarization-OAM (orbital angular momentum) entanglement are the exact solutions of the vector Helmholtz equation. Decomposition of arbitrary vector beams in the initial plane z = 0 into these polarization-invariant beams with phase and polarization singularities was used to analyze the evolution of the polarization of light within the framework of the 2 × 2 coherency matrix formalism. It is shown that the 2D degree of polarization decreases with distance if the incident vector beam is not the modal solution. The close relationship of the degree of polarization with the quantum-mechanical purity parameter is emphasized.

Propagation of Terahertz Surface Plasmon Pulses in a Plasmonic Fiber

“…Future research may be related to the consideration of pulse propagation taking into account higher-order dispersion terms and structured vector vortex modes of SPPs in a plasmonic fiber. Of particular interest is the consideration of structured vortex beams with orbital angular momentum [24,[29][30][31][32][33] and the effects of the Goos-Hanchen shift [34][35][36][37]. Tunable resonance Goos-Hanchen and Imbert-Fedorov shifts for THz beams reflected from graphene plasmonic metasurfaces were investigated in [34].…”

Nonparaxial Focusing of Partially Coherent Gaussian Schell-Model and Bessel-Correlated Beams in Free Space

“…Future research can be related to the consideration of focusing partially coherent and partially polarized vector beams [45]. Of practical interest is the consideration of structured vortex beams with spin angular momentum (SAM) and orbital angular momentum (OAM) [46][47][48], partially coherent accelerating beams [49], beams possessing self-healing abilities in a turbulent media [50], and spatiotemporal optical vortex beams [51].…”

Nonparaxial Propagation of Bessel Correlated Vortex Beams in Free Space

“…Future research may be related to the consideration of the propagation of vector vortex partially coherent and partially polarized beams. Of particular interest is the consideration of structured vortex flows with an orbital angular momentum [ 76 , 77 , 78 , 79 , 80 , 81 , 82 ] and the effects of nonparaxiality and depolarization during propagation [ 83 , 84 ]. Other important topics are the coherence and polarization effects in gradient-index medium [ 85 ], plasmonic structures [ 86 , 87 ], in turbulent media, etc.…”