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arXiv · 2203.11848

Electronic structure and open-orbit Fermi surface topology in isostructural semimetals NbAs$_2$ and W$_2$As$_3$ with extremely large magnetoresistance

Rui Lou·Yiyan Wang·Lingxiao Zhao·Chenchao Xu·Man Li·Xiaoyang Chen·Anmin Zhang·Yaobo Huang·Chao Cao·Genfu Chen·Tianlong Xia·Qingming Zhang·Hong Ding·Shancai Wang
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Abstract

In transition-metal dipnictides $TmPn_2$ ($Tm$ = Ta, Nb; $Pn$ = P, As, Sb), the origin of extremely large magnetoresistance (XMR) is yet to be studied by the direct visualization of the experimental band structures. Here, using angle-resolved photoemission spectroscopy, we map out the three-dimensional electronic structure of NbAs$_2$. The open-orbit topology contributes to a non-negligible part of the Fermi surfaces (FSs), like that of the isostructural compound MoAs$_2$, where the open FS is proposed to likely explain the origin of XMR. We further demonstrate the observation of open characters in the overall FSs of W$_2$As$_3$, which is also a XMR semimetal with the same space group of $C$12/$m$1 as $TmPn_2$ family and MoAs$_2$. Our results suggest that the open-orbit FS topology may be a shared feature between XMR materials with the space group of $C$12/$m$1, and thus could possibly play a role in determining the corresponding XMR effect together with the electron-hole compensation.

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Rui Lou, Yiyan Wang, Lingxiao Zhao, Chenchao Xu, Man Li, Xiaoyang Chen, Anmin Zhang, Yaobo Huang, Chao Cao, Genfu Chen, Tianlong Xia, Qingming Zhang, Hong Ding, Shancai Wang. 2022-03-22. Electronic structure and open-orbit Fermi surface topology in isostructural semimetals NbAs$_2$ and W$_2$As$_3$ with extremely large magnetoresistance. https://doi.org/10.1063/5.0087141

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