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arXiv · 1506.01751

Electron-hole compensation effect between topologically trivial electrons and nontrivial holes in NbAs

Yongkang Luo·N. J. Ghimire·M. Wartenbe·Hongchul Choi·M. Neupane·R. D. McDonald·E. D. Bauer·Jianxin Zhu·J. D. Thompson·F. Ronning
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Abstract

Via angular Shubnikov-de Hass (SdH) quantum oscillations measurements, we determine the Fermi surface topology of NbAs, a Weyl semimetal candidate. The SdH oscillations consist of two frequencies, corresponding to two Fermi surface extrema: 20.8 T ($\alpha$-pocket) and 15.6 T ($\beta$-pocket). The analysis, including a Landau fan plot, shows that the $\beta$-pocket has a Berry phase of $\pi$ and a small effective mass $\sim$0.033 $m_0$, indicative of a nontrivial topology in momentum space; whereas the $\alpha$-pocket has a trivial Berry phase of 0 and a heavier effective mass $\sim$0.066 $m_0$. From the effective mass and the $\beta$-pocket frequency we determine that the Weyl node is 110.5 meV from the chemical potential. A novel electron-hole compensation effect is discussed in this system, and its impact on magneto-transport properties is addressed. The difference between NbAs and other monopnictide Weyl semimetals is also discussed.

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Yongkang Luo, N. J. Ghimire, M. Wartenbe, Hongchul Choi, M. Neupane, R. D. McDonald, E. D. Bauer, Jianxin Zhu, J. D. Thompson, F. Ronning. 2015-06-04. Electron-hole compensation effect between topologically trivial electrons and nontrivial holes in NbAs. https://doi.org/10.1103/physrevb.92.205134

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