Abstract
mStudies of the deformation for the ternary chalcogenide crystals Tl4SnSe3 was performed under illumination of the two type of pulsed lasers: nanosecond Nd: YAG laser generating at 1064 nm and nanosecond CO2 laser generating at 10.6 mu m and its fourth harmonic at 2.65 mu m. The dilatometry studies have shown nonlinear dependence of laser stimulated deformation versus the pump power density. The dependence has an opposite feature which may indicate on an excitation of the different systems by these two lasers: electronic and phonon ones. The possible mechanisms are based on the excitations of the electron and phonon subsystem and formation of the photopolarized states which change the deformation.