Laser-induced bleaching and thermo-stimulated recovery of luminescent centers in bismuth-doped optical fibers

Abstract

In this paper, we report the detailed study of photobleaching and recovery in bismuth-doped fibers that proved to be a unique laser media for the near IR spectral regions unreachable for rare-earth-doped lasers. The laser-induced bleaching and recovery dynamics of the characteristic absorption and emission bands assigned to different types of the bismuth-related active centers were obtained. By analyzing the Raman-scattering spectra of the bleached bismuth-doped fibers, the intensity-dependence of the photobleaching rate and the experimentally determined activation energy of the recovery process and underlying mechanisms of these phenomena are discussed. Furthermore, a bleaching–recovery cycling and “memory effect” are demonstrated.