Nanowerk August 12, 2019
The most common manifestation of subwavelength disorder is Rayleigh light scattering, which is observed in nearly all waveguiding technologies today and can lead to both irreversible radiative losses as well as undesirable intermodal coupling. A team of researchers in the US (University of Illinois, University of Maryland, NIST) has demonstrated an optomechanical approach for dynamically suppressing Rayleigh backscattering within dielectric resonators by locally breaking the time-reversal symmetry in a silica resonator through a Brillouin scattering interaction that is available in all materials. They confirmed complete suppression of Rayleigh backscattering in their experiment through two independent measurements—the elimination of a commonly seen normal-mode splitting or “doublet” effect and by measurement of the reduction in intrinsic optical loss. The results provide new evidence that it is possible to dynamically suppress Rayleigh backscattering within any optical dielectric medium using time-reversal symmetry breaking, for achieving robust light propagation despite scatterers or defects…read more. Open Access TECHNICAL ARTICLE
Rayleigh backscattering in a whispering-gallery resonator (WGR) and concept for optomechanical suppression. Credit: Optica https://doi.org/10.1364/OPTICA.6.001016