Anisotropic Magnetoresistivity in Semimetal TaSb2

作者:Liu, Xia-Yin; Wang, Jia-Lu; You, Wei; Wang, Ting-Ting; Yang, Hai-Yang; Jiao, Wen-He; Mao, Hong-Ying; Zhang, Li; Cheng, Jie; Li, Yu-Ke*
来源:Chinese Physics Letters, 2017, 34(12): 127501.
DOI:10.1088/0256-307X/34/12/127501

摘要

We investigate the anisotropic magnetic transports in topological semimetal TaSb2. The compound shows the large magnetoresistance (MR) without saturation and the metal-insulator-like transition no matter whether the magnetic field is parallel to c-axis or a-axis, except that the MR for B parallel to c is almost twice as large as that of B parallel to a at low temperatures. The adopted Kohler's rule can be obeyed by the MR at distinct temperatures for B parallel to c, but it is slightly violated as B parallel to a The angle-dependent MR measurements exhibit the two-fold rotational symmetry below 70 K, consistent with the monoclinic crystal structure of TaSb2. The dumbbell-like picture of angle-dependent MR in TaSb2 suggests a strongly anisotropic Fermi surface at low temperatures. However, it finally loses the two-fold symmetry over 70 K, implying a possible topological phase transition at around the temperature where Tm is related to a metal-insulator-like transition under magnetic fields.