In this article, we present the optical study of undoped and Au-doped rhenium disulphide (ReS2 and ReS2:Au) using temperature- and polarization-dependent thermoreflectance (PTR) and reflectance (R) measurements. We have observed the indirect band gaps (Eg||, E g⊥), and direct band-edge excitonic transitions (E ex1, Eex2, Eex 3 and Eex4) at various polarization angles. The amplitudes of Eex1 and Eex2 transitions have an orthogonal characteristic and follow the Malus rule. A small blue-shift of indirect band gaps has been observed for the ReS2:Au sample, we believe that this result is contributed from the doping effects. We also measured the temperature-dependent PTR spectra in the temperature range from 55 to 300 K, and determined the temperature dependences of the transition energies and broadening parameters of Eex1 and E ex2 transitions. Reflectance measurements at various polarizations have been performed to confirm our observations.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)