Structural phase transition in Bi₂Te₃ under high pressure

Abstract

Structural change in Bi₂Te₃ under high pressure up to 16.6 GPa has been studied by powder x-ray diffraction. We observed two times of phase transitions at room temperature at the pressures of 8 and 14 GPa, respectively. According to our preliminary result on electrical resistance, it is reasonable to suppose that superconducting transition with T _c =2.8 K at the pressures of 10.2 GPa is observed in phase II. On the other hand, we found anomalies of the pressure dependences of lattice parameters and volume at around 2 GPa, which probably means the change in electrical structure on the Fermi surface.

^†This paper was presented at the XLVI^th European High Pressure Research Group (EHPRG 46) Meeting, Valencia (Spain), 7–12 September, 2008.

Keywords:

• pressure-induced phase transition
• superconductor
• thermoelectric material
• high-pressure x-ray diffraction
• hydrostatic pressure

Acknowledgements

The present work has been done under Proposal No. 2007G664 of the Photon Factory. This research was partially supported by Grant-in-Aids for Science Research on Priority Areas: ‘Novel State of Matter Induced by Frustration’ and ‘New Materials Science Using Regulated Nano Space-Strategy in Ubiquitous Elements’, from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. It is also supported by the Grant for Promotion of Niigata University Research Projects.

Notes

^†This paper was presented at the XLVI^th European High Pressure Research Group (EHPRG 46) Meeting, Valencia (Spain), 7–12 September, 2008.