Abstract
Optical and Hall effect measurements have been performed on single crystals of Pb0.77Sn0.23Se, a IV-VI mixed chalcogenide. The temperature-dependent (10-300 K) reflectance was measured over 40-7000 cm-1 (5-870 meV) with an extension to 15 500 cm-1 (1.92 eV) at room temperature. The reflectance was fitted to the Drude-Lorentz model using a single Drude component and several Lorentz oscillators. The optical properties at the measured temperatures were estimated via Kramers-Kronig analysis as well as by a Drude-Lorentz fit. The carriers were p type with the carrier density determined by Hall measurements. A signature of valence intraband transition is found in the low-energy optical spectra. It is found that the valence-conduction band transition energy as well as the free-carrier effective mass reach minimum values at 100 K, suggesting temperature-driven band inversion in the material. Density functional theory calculations for the electronic band structure are also presented.
Original language | English (US) |
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Article number | 235143 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 90 |
Issue number | 23 |
DOIs | |
State | Published - Dec 23 2014 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics