Laser-induced phase transitions in vitreous Se films obtained by vacuum-thermal evaporation

The results of the study of vitreous Se films obtained by a method of vacuum-thermal evaporation after their laser modification are presented. It is shown for the first time that a low-power laser irradiation of the film at a wavelength of 632.8 nm and room temperature results in a nucleation and growth of nanocrystallites of monoclinic and rhombohedral Se in an amorphous matrix of the film. The formation of the stable hexagonal Se phase is not observed. The appearance of nanocrystallites with an average size of $\sim$20–30 nm is accompanied by a growth of a reflection coefficient of the film. The established new optical and structural properties of the formed films are stable in time at room temperature.