Pressure-induced superconductivity in non-stoichiometric bismuth telluride Bi35Te65

18th APS-SCCM; 24th AIRAPT

Yamada, Y.^3 ; Einaga, M.^1 ; Ohmura, A.^2 ; Ishikawa, F.^3 ; Nakayama, A.^2 ; Yamada, Yuh^3 ; Nakano, S.^4 ; Matsushita, A.^4 ; Shimizu, K.^1

KYOKUGEN, Center for Quantum Science and Technology under Extreme Conditions, Osaka University, Osaka

562-8531, Japan^1

Center for Transdisciplinary Research, Niigata University, Niigata

950-2181, Japan^2

Department of Physics, Niigata University, Niigata

950-2181, Japan^3

National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba

305-0044, Japan^4

关键词: Electrical resistivity measurements;    High-pressure phasis;    P type semiconductor;    Pressure induced superconductivity;    Rhombohedral structures;    Structural phase transition;    Superconducting transitions;    X-ray diffraction studies;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/19/192003/pdf
DOI  :  10.1088/1742-6596/500/19/192003

来源: IOP

【 摘 要 】

We performed x-ray diffraction study and electrical resistivity measurement of non-stoichiometric n-type Bi35Te65under high pressure to investigate pressure-induced superconductivity and structural phase transition. Stoichiometric bismuth telluride (Bi2Te3), which is a p-type semiconductor, has the rhombohedral structure with space group R-3m at ambient condition. Pressure-induced superconductivity of stoichiometric p-type Bi2Te3occurs in the high-pressure phases which appear above 8 GPa. Bi35Te65has also the R-3m structure at ambient condition with electron carriers. X-ray diffraction study shows that the R-3m structure remains stable up to 8 GPa at room temperature. The superconducting transition in n-type Bi35Te65is observed above 6 GPa; the transition temperature is 2.9 K at 6 GPa. The electrical resistivity at room temperature decreases rapidly at pressures from 7 to 8 GPa, indicating the occurrence of structural phase transition. It suggests that the superconducting transition at 6 GPa occurs at the ambient pressure phase with the R-3m structure.