Optical properties of thin films of system (As2Se3)80−x(As2Te3)x(SnTe)20 prepared by PLD

Thin amorphous films from system (As2Se3)80−x(As2Te3)x(SnTe)20 were prepared by pulsed laser deposition (PLD) from their bulk glasses and their optical properties were studied by spectral ellipsometry. Spectral dependencies of refractive index, absorption and extinction coefficient and optical gap (1.41–1.66 eV for (As2Se3)80−x(As2Te3)x(SnTe)20 with x = 20 resp. x = 0) were calculated from optical tansmittance, from ellipsometric data by Tauc method. High values of refractive index n0 (2.49–2.60) and of non-linear χ(3) coefficient of index of refraction (4.9–7.5 × 10−12 esu for the glass (As2Se3)80−x(As2Te3)x(SnTe)20 with x = 0 resp. x = 20) made studied thin films of system (As2Se3)80−x(As2Te3)x(SnTe)20 promising candidates for application in optics and optoelectronics.