Breakdown of Three-dimensional Dirac Semimetal State in pressurized Cd3As2

Shan Zhang; Qi Wu; Leslie Schoop; Mazhar N. Ali; Youguo Shi; Ni Ni; Quinn Gibson; Vladimir Sidorov; Wei Yi; Jing Guo; Yazhou Zhou; Peiwen Gao; Dachun Gu; Chao Zhang; Sheng Jiang; Ke Yang; Aiguo Li; Yanchun Li; Xiaodong Li; Jing Liu; Xi Dai; Zhong Fang; Robert J. Cava; Liling Sun; Zhongxian Zhao

doi:10.1103/physrevb.91.165133

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arXiv · 1410.3213

Breakdown of Three-dimensional Dirac Semimetal State in pressurized Cd3As2

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Abstract

We report the first observation of a pressure-induced breakdown of the 3D-DSM state in Cd3As2, evidenced by a series of in-situ high-pressure synchrotron X-ray diffraction (XRD) and single crystal transport measurements. We find that Cd3As2 undergoes a structural phase transition from a metallic tetragonal (T) phase in space group I41/acd to a semiconducting monoclinic (M) phase in space group P21/c at critical pressure 2.57 GPa, above this pressure, an activation energy gap appears, accompanied by distinct switches in Hall resistivity slope and electron mobility. These changes of crystal symmetry and corresponding transport properties manifest the breakdown of the 3D-DSM state in pressurized Cd3As2.

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Shan Zhang, Qi Wu, Leslie Schoop, Mazhar N. Ali, Youguo Shi, Ni Ni, Quinn Gibson, Vladimir Sidorov, Wei Yi, Jing Guo, Yazhou Zhou, Peiwen Gao, Dachun Gu, Chao Zhang, Sheng Jiang, Ke Yang, Aiguo Li, Yanchun Li, Xiaodong Li, Jing Liu, Xi Dai, Zhong Fang, Robert J. Cava, Liling Sun, Zhongxian Zhao. 2015-06-22. Breakdown of Three-dimensional Dirac Semimetal State in pressurized Cd3As2. https://doi.org/10.1103/physrevb.91.165133

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