Pressure Induced Spectral Redistribution due to Te2 Dimer Breaking in AuTe2

Daiki Ootsuki*, Hidekazu Okamura, Shogo Mitsumoto, Yuka Ikemoto, Taro Moriwaki, Masashi Arita, Teppei Yoshida, Kazutaka Kudo, Hiroyuki Ishii, Minoru Nohara, Takashi Mizokawa

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

We report the electronic structure of a natural mineral calaverite AuTe2 under high pressure by means of the infrared spectroscopy. The optical conductivity at ambient pressure shows a Drude response and a hump structure around 0.2 eV. These characteristic results are more prominent in going from high temperature to low temperature. The Drude response increases with pressure, which corresponds to the reduction of the electrical resistivity. Meanwhile, the hump structure is suppressed and merged into the Drude response with increasing pressure. Further applying pressure up to 3 GPa, the hump structure almost disappears. We have fitted the optical conductivity by using the Drude–Lorentz model and obtained the plasma frequency ωp and the scattering rate γ. The squared plasma frequency !2p increases and the scattering rate γ decreases with pressure. Our results suggest that the suppression of the electrical resistivity under pressure is mainly due to the increase of the carrier density n and the reduction of the scattering rate γ. By comparing the optical conductivity with the band structure calculation and the photoemission spectroscopy, we discuss the low-energy excitation corresponding to the hump structure and the variation of the Drude component in the optical conductivity.

Original languageEnglish
Article number114705
Journaljournal of the physical society of japan
Volume90
Issue number11
DOIs
Publication statusPublished - 2021 Nov 15

ASJC Scopus subject areas

  • General Physics and Astronomy

Fingerprint

Dive into the research topics of 'Pressure Induced Spectral Redistribution due to Te2 Dimer Breaking in AuTe2'. Together they form a unique fingerprint.

Cite this