Influence of the Veigert Effect and Spontaneous Periodic Structures on the Spectral Photoadaptation in Thin Light-sensitive AgCl–Ag Films

摘要

The absorption spectrum of thin AgCl films doped with granulated Ag and irradiated by linearly polarized monochromatic light of frequency 0 at the low-frequency wing of the colloidal band is studied. Itis shown that the appearance of a polarized spectral hole at = 0 in the spectral band during initial stages of irradiation is connected with a directed reorientation of initially randomly distributed chains consisting of very small granules of Ag [the Veigert effect (VE)]. A simple model is proposed that allows one to predict the shape of polarized bands upon irradiation and to separate the contributions of homogeneous and inhomogeneous broadening of the colloidal band. It is found that, after a certain threshold exposure, the evolution of the polarized spectral hole is connected with formation of spontaneous periodic structures on the waveguide TE modes scattered in the film, while the linear chains responsible for the transverse VE are destroyed. The kinetics of the spectral hole evolution at different stages of irradiation is studied.