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arXiv · 2107.11957

Shubnikov-de Haas Oscillations and Nontrivial Topological State in a New Weyl Semimetal Candidate SmAlSi

Longmeng Xu·Haoyu Niu·Yuming Bai·Haipeng Zhu·Songliu Yuan·Xiong He·Yang Yang·Zhengcai Xia·Lingxiao Zhao·Zhaoming Tian
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Abstract

We perform the quantum magnetotransport measurements and first-principles calculations on high quality single crystals of SmAlSi, a new topological Weyl semimetal candidate. At low temperatures, SmAlSi exhibits large non-saturated magnetoresistance (MR)~5200% (at 2 K, 48 T) and prominent Shubnikov-de Haas (SdH) oscillations, where MRs follow the power-law field dependence with exponent 1.52 at low fields (μ0H < 15 T) and linear behavior 1 under high fields (μ0H > 18 T). The analysis of angle dependent SdH oscillations reveal two fundamental frequencies originated from the Fermi surface (FS) pockets with non-trivial π Berry phases, small cyclotron mass and electron-hole compensation with high mobility at 2 K. In combination with the calculated nontrivial electronic band structure, SmAlSi is proposed to be a paradigm for understanding the Weyl fermions in the topological materials.

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Longmeng Xu, Haoyu Niu, Yuming Bai, Haipeng Zhu, Songliu Yuan, Xiong He, Yang Yang, Zhengcai Xia, Lingxiao Zhao, Zhaoming Tian. 2021-08-06. Shubnikov-de Haas Oscillations and Nontrivial Topological State in a New Weyl Semimetal Candidate SmAlSi. https://doi.org/10.1088/1361-648x%2Fac987a

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