Introduction. The photorefractive parameters of the Sn2P2S6 single crystals modified by different ways (doping, post-growth treatment) permit to realize the dynamic interferometers. A specific interest represent the samples with strong compensation process.
Purpose. This article is devoted to consideration of usage of the Sn2P2S6 crystal modified by an indiffusion of the Cu atoms as an active element of the dynamic interferometer, and analyzing of its frequency parameters.
Results. The diffusion-modified Sn2P2S6 sample demonstrates an increased compensation of the photorefractive gratings that manifests itself in the complex dynamics of the stationary energy transfer. This peculiarity is also observed in the frequency spectra measured at the phase modulation of the interacting beams. These frequency spectra of the first and second harmonics, as well as the corresponding stationary component, are obtained and analysed.
Conclusion. The dynamic interferometer on the basis of the Cu-doped Sn2P2S6 with strong gain compensation allows to construct the band-pass frequency filters, and also to study the two-wave mixing gain spectrum using frequency-modulation technique
Keywords: dynamic interferometer, photorefractive effect, two-wave mixing, phase modulation, tin thiohypodiphosphate