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arXiv · 1801.02018

Band dependence of charge density wave in quasi-one-dimensional Ta2NiSe7 probed by orbital magnetoresistance

Jiaming He·Yiran Zhang·Libin Wen·Yusen Yang·Jinyu Liu·Yueshen Wu·Hailong Lian·Hui Xing·Shun Wang·Zhiqiang Mao·Ying Liu
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Abstract

Ta2NiSe7 is a quasi-one-dimensional (quasi-1D) transition-metal chalcogenide with Ta and Ni chain structure. An incommensurate charge-density wave (CDW) in this quasi-1D structure was well studied previously using tunnelling spectrum, X-ray and electron diffraction, whereas its transport property and the relation to the underlying electronic states remain to be explored. Here we report our results of magnetoresistance (MR) on Ta2NiSe7. A breakdown of the Kohler's rule is found upon entering the CDW state. Concomitantly, a clear change of curvature in the field dependence of MR is observed. We show that the curvature change is well described by two-band orbital MR, with the hole density being strongly suppressed in the CDW state, indicating that the $p$ orbitals from Se atoms dominate the change in transport through the CDW transition.

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Jiaming He, Yiran Zhang, Libin Wen, Yusen Yang, Jinyu Liu, Yueshen Wu, Hailong Lian, Hui Xing, Shun Wang, Zhiqiang Mao, Ying Liu. 2018-01-06. Band dependence of charge density wave in quasi-one-dimensional Ta2NiSe7 probed by orbital magnetoresistance. https://doi.org/10.1063/1.4990801

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