Thermoreflectance spectra of rf-sputtered epitaxial single-crystal films ofPbxSn1−xTe

Abstract

Thermoreflectance spectra of radio-frequency sputtered epitaxial single-crystal films of ${\mathrm{Pb}}_{0.83}$${\mathrm{Sn}}_{0.17}$Te from 1.5 to 6.0 eV, at room temperature and 100 K, have been measured and studied. $\ensuremath{\Delta}{\ensuremath{\epsilon}}_{1}$ and $\ensuremath{\Delta}{\ensuremath{\epsilon}}_{2}$ have been obtained through a Kramers-Kronig analysis of the experimental room-temperature $\frac{\ensuremath{\Delta}R}{R}$ spectra. A line-shape analysis of the ${E}_{2}$ structure has been performed in conjunction with an exact derivative procedure of the interband dielectric function at Van Hove singularities. Temperature coefficients have been measured and reported.