Thumbnail
Access Restriction
Open

Author Mosca, S. ♦ De Rosa, R. ♦ Milano, L. ♦ Canuel, B. ♦ Genin, E. ♦ Karimi, E. ♦ Piccirillo, B. ♦ Santamato, E. ♦ Marrucci, L.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY ♦ CONVERSION ♦ CRYSTALS ♦ DEPOLARIZATION ♦ FOCUSING ♦ GALLIUM COMPOUNDS ♦ GARNETS ♦ INTERFEROMETRY ♦ LASER RADIATION ♦ LASER-RADIATION HEATING ♦ NONLINEAR PROBLEMS ♦ ORBITAL ANGULAR MOMENTUM ♦ PHOTON BEAMS ♦ PHOTONS ♦ POLARIZATION ♦ RODS ♦ SPIN ♦ TEMPERATURE GRADIENTS ♦ TERBIUM COMPOUNDS ♦ ANGULAR MOMENTUM ♦ BEAMS ♦ BOSONS ♦ ELECTROMAGNETIC RADIATION ♦ ELEMENTARY PARTICLES ♦ HEATING ♦ MASSLESS PARTICLES ♦ MINERALS ♦ PARTICLE PROPERTIES ♦ PLASMA HEATING ♦ RADIATIONS ♦ RARE EARTH COMPOUNDS ♦ SILICATE MINERALS
Abstract In this paper, we present experimental evidence of a third-order nonlinear optical process, self-induced spin-to-orbital conversion (SISTOC) of the photon angular momentum. This effect is the physical mechanism at the origin of the depolarization of very intense laser beams propagating in isotropic materials. The SISTOC process, like self-focusing, is triggered by laser heating leading to a radial temperature gradient in the medium. In this work we tested the occurrence of SISTOC in a terbium-gallium-garnet rod for an impinging laser power of about 100 W. To study the SISTOC process we used different techniques: polarization analysis, interferometry, and tomography of the photon orbital angular momentum. Our results confirm, in particular, that the apparent depolarization of the beam is due to the occurrence of maximal entanglement between the spin and orbital angular momentum of the photons undergoing the SISTOC process. This explanation of the true nature of the depolarization mechanism could be of some help in finding novel methods to reduce or to compensate for this usually unwanted depolarization effect in all cases where very high laser power and good beam quality are required.
ISSN 10502947
Educational Use Research
Learning Resource Type Article
Publisher Date 2010-10-15
Publisher Place United States
Journal Physical Review. A
Volume Number 82
Issue Number 4


Open content in new tab

   Open content in new tab