Fundamental Optical Functions and Fine-Structure Parameters of Strontium-Selenide Crystal Transition Bands in the 0-40 eV Range

摘要

The spectral complex of fundamental optical functions of strontium-selenide (SrSe) crystal in the range 0-40 eV was determined. Spectra of the imaginary parts of three functions [transverse dielectric permittivity epsilon(2)(E) and longitudinal volume -Im epsilon(-1) and surface -Im (1 + epsilon)(-1) characteristic electron energy losses] of SrSe crystal were deconvoluted into 36 elementary bands. Energies of maxima E (i) , half-widths H (i) , amplitudes I (i) , areas S (i) , and oscillator strengths f (i) were determined for every band of the three spectra. The main spectral features of the optical functions and 36 elementary bands of SrSe in the range 3-35 eV due to excitons and transverse and longitudinal interband transitions were established. The calculations were based on experimental reflectance spectra and used the Kramers-Kronig integral relations, a modified combined Argand diagram method, and a number of computer programs.