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DOE OSTI · 1044420

The comprehensive phase evolution for Bi[subscript 2]Te[subscript 3] topological compound as function of pressure

Zhang, S J·Zhang, J L·Yu, X H·Zhu, J·Kong, P P·Feng, S M·Liu, Q Q·Yang, L X·Wang, X C·Cao, L Z·Yang, W G·Wang, L·Mao, H K·Zhao, Y S·Liu, H Z·Dai, X·Fang, Z·Zhang, S C·Jin, C Q
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Abstract

The recently discovered three-dimensional topological insulator Bi{sub 2}Te{sub 3} is studied as function of pressure in terms of crystal structures, resistance, and Hall coefficient. The superconductivity is found in phase I (ambient phase) Bi{sub 2}Te{sub 3} with T{sub c}-3 K, which is related to the topological features. The evolution of crystal structure with pressure is investigated by high pressure synchrotron radiation experiments that reveal structural transitions occurring at about 8 GPa, 13 GPa, and 16 GPa, respectively. Furthermore, the high pressure phases of Bi{sub 2}Te{sub 3} are also superconducting but with much higher T{sub c}-8 K. The superconducting transitions are compared with those for Bi, Te elements. A global phase diagram of Bi{sub 2}Te{sub 3} as function of pressure up to 30 GPa is obtained.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSBISMUTH COMPOUNDSCRYSTAL STRUCTUREELECTRIC CONDUCTIVITYHALL EFFECTPHASE DIAGRAMSPHASE TRANSFORMATIONSSUPERCONDUCTIVITYSYNCHROTRON RADIATIONTRANSITION TEMPERATURE

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Zhang, S J, Zhang, J L, Yu, X H, Zhu, J, Kong, P P, Feng, S M, Liu, Q Q, Yang, L X, Wang, X C, Cao, L Z, Yang, W G, Wang, L, Mao, H K, Zhao, Y S, Liu, H Z, Dai, X, Fang, Z, Zhang, S C, Jin, C Q. 2012-06-26. The comprehensive phase evolution for Bi[subscript 2]Te[subscript 3] topological compound as function of pressure. https://doi.org/10.1063/1.4726258

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