Quantum oscillations and nontrivial topological state in a compensated semimetal TaP2
Autor: | Hongyuan Wang, Wei Xia, Na Yu, Jiuyang Zhang, Xiaofei Hou, Zhenhai Yu, Xia Wang, Yanfeng Guo, Qifeng Liang, Yishi Lin, Xiaolei Liu, Yuhua Zhen, Zhiqiang Zou, Hao Su, Yihua Wang |
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Rok vydání: | 2019 |
Předmět: |
Chiral anomaly
Physics Strongly Correlated Electrons (cond-mat.str-el) Condensed Matter - Mesoscale and Nanoscale Physics Magnetoresistance FOS: Physical sciences Quantum oscillations 02 engineering and technology Electron 021001 nanoscience & nanotechnology Topology 01 natural sciences Brillouin zone Condensed Matter - Strongly Correlated Electrons Geometric phase Ab initio quantum chemistry methods Topological insulator Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences Condensed Matter::Strongly Correlated Electrons 010306 general physics 0210 nano-technology |
Zdroj: | Physical Review B. 100 |
ISSN: | 2469-9969 2469-9950 |
Popis: | We report systematic magneto-transport measurements and ab initio calculations on single-crystalline TaP2, a new member of the transition-metal dipnictides. We observed unsaturated magnetoresistance (MR) reaching ~ 700% at a magnetic field (B) of 9 T at 2 K along with striking Shubnikov-de Hass (SdH) oscillations. Our analysis on the SdH oscillations reveals nonzero Berry phase, indicating nontrivial band topology. The analysis also uncovers three fundamental magnetic oscillation frequencies of 72 T, 237 T, and 356 T, consistent with the theoretical calculations which reveal one hole pocket and two electron pockets at the L point and one electron pocket at the Z point of the Brillouin zone. We also found negative longitudinal MR (n-MR) within a narrow window of the angles between B and the electric current (I). The n-MR could be fitted with the Adler-Bell-Jackiw chiral anomaly equation but the origin remains yet ambiguous. The ab inito calculations suggest TaP2 as a weak topological insulator with the Z2 indices of (0; 111), which exhibits topological surface states on the (001) surface. 22 pages, 6 figures, 1 table |
Databáze: | OpenAIRE |
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