title: Superconductivity in HfTe5across weak to strong topological insulator transition induced via pressures.
abstract: Recently, theoretical studies show that layered HfTe5is at the boundary of weak &strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe5are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic &crystal structures for HfTe5with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe5crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe5transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe5is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Long
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: L X
authors.initials: LX
authors.lastname: Zhao
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: S M
authors.initials: SM
authors.lastname: Nie
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: S J
authors.initials: SJ
authors.lastname: Zhang
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y X
authors.initials: YX
authors.lastname: Weng
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: M L
authors.initials: ML
authors.lastname: Jin
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: W M
authors.initials: WM
authors.lastname: Li
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Q Q
authors.initials: QQ
authors.lastname: Liu
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y W
authors.initials: YW
authors.lastname: Long
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: R C
authors.initials: RC
authors.lastname: Yu
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: C Z
authors.initials: CZ
authors.lastname: Gu
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: F
authors.initials: F
authors.lastname: Sun
authors.affiliation: Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, China.
authors.forename: W G
authors.initials: WG
authors.lastname: Yang
authors.affiliation: Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, China.
authors.forename: H K
authors.initials: HK
authors.lastname: Mao
authors.affiliation: Department of Materials Science, Jilin University, Changchun 130012, China.
authors.forename: X L
authors.initials: XL
authors.lastname: Feng
authors.affiliation: Department of Materials Science, Jilin University, Changchun 130012, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Materials Science, Jilin University, Changchun 130012, China.
authors.forename: W T
authors.initials: WT
authors.lastname: Zheng
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: H M
authors.initials: HM
authors.lastname: Weng
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: X
authors.initials: X
authors.lastname: Dai
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Fang
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: G F
authors.initials: GF
authors.lastname: Chen
authors.affiliation: Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter, Beijing, China.
authors.forename: C Q
authors.initials: CQ
authors.lastname: Jin