<title>Temperature dependences of optical absorption and its light-induced changes in sillenite crystals</title>

Abstract

Results of experimental investigations of temperature dependences of optical absorption coefficients and their light-induced changes for Bi₁₂SiO₂₀, Bi₁₂TiO₂₀:Zn, and Bi₁₂TiO₂:Ca crystals are presented. Semiconductor light diodes emitting quasimonochromatic radiation in red (625 nm), yellow (570 nm), green (505 and 515 nm), and blue (470 nm) ranges of the spectrum were used as light sources. A theoretical model of thermal- and light-induced changes in the optical absorption is considered that describes well the observed temperature dependences of the optical absorption for the Bi₁₂SiO₂₀ and Bi₁₂TiO₂₀:Ca crystals and the dynamics of light-induced changes in light absorption for the Bi₁₂TiO₂:Ca crystal at a wavelength of 470 nm and temperatures in the interval from 24 to 100°C.