Quantum transport in a compensated semimetal W2As3 with nontrivial Z2 indices
Abstract
We report a topological semimetal W2As3 with a space group C 2 /m . Based on the first-principles calculations, band crossings are partially gapped when spin-orbit coupling is included. The Z2 indices at the electron filling are [1;111], characterizing a strong topological insulator and topological surface states. From the magnetotransport measurements, nearly quadratic field dependence of magnetoresistance (MR) (B ∥[200 ] ) at 3 K indicates an electron-hole compensated compound whose longitudinal MR reaches 11 500% at 3 K and 15 T. In addition, multiband features are detected from the high-magnetic-field Shubnikov-de Haas (SdH) oscillation, Hall resistivity, and band calculations. A nontrivial π Berry's phase is obtained, suggesting the topological feature of this material. A two-band model can fit well the conductivity and Hall coefficient. Our experiments manifest that the transport properties of W2As3 are in good agreement with the theoretical calculations.
- Publication:
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Physical Review B
- Pub Date:
- September 2018
- DOI:
- 10.1103/PhysRevB.98.115145
- arXiv:
- arXiv:1810.00665
- Bibcode:
- 2018PhRvB..98k5145L
- Keywords:
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- Condensed Matter - Materials Science
- E-Print:
- 8 pages, 5 figures