title: Anomalous anisotropic compression behavior of superconducting CrAs under high pressure.
abstract: CrAs was observed to possess the bulk superconductivity under high-pressure conditions. To understand the superconducting mechanism and explore the correlation between the structure and superconductivity, the high-pressure structural evolution of CrAs was investigated using the angle-dispersive X-ray diffraction (XRD) method. The structure of CrAs remains stable up to 1.8 GPa, whereas the lattice parameters exhibit anomalous compression behaviors. With increasing pressure, the lattice parameters a and c both demonstrate a nonmonotonic change, and the lattice parameter b undergoes a rapid contraction at ∼ 0.18-0.35 GPa, which suggests that a pressure-induced isostructural phase transition occurs in CrAs. Above the phase transition pressure, the axial compressibilities of CrAs present remarkable anisotropy. A schematic band model was used to address the anomalous compression behavior of CrAs. The present results shed light on the structural and related electronic responses to high pressure, which play a key role toward understanding the superconductivity of CrAs.
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, People's Republic of China;
authors.forename: Zhenhai
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Beijing National Lab for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China;
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, People's Republic of China;
authors.forename: Qingyang
authors.initials: Q
authors.lastname: Hu
authors.affiliation: Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, People's Republic of China;
authors.forename: Jinggeng
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, People's Republic of China;
authors.forename: Chunyu
authors.initials: C
authors.lastname: Li
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China;
authors.forename: Ke
authors.initials: K
authors.lastname: Yang
authors.affiliation: Beijing National Lab for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China;
authors.forename: Jinguang
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Beijing National Lab for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, People's Republic of China;
authors.forename: Jianlin
authors.initials: J
authors.lastname: Luo
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, People's Republic of China; State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, People's Republic of China wanglin@hpstar.ac.cn hmao@carnegiescience.edu.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, People's Republic of China; wanglin@hpstar.ac.cn hmao@carnegiescience.edu.
authors.forename: Ho-Kwang
authors.initials: HK
authors.lastname: Mao
keywords: CrAs; anisotropic compression behavior; high pressure; phase transformation