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arXiv · 1609.03716

Temperature effect on lattice and electronic structures of WTe$_2$ from first-principles study

Gang Liu·Huimei Liu·Jian Zhou·Xiangang Wan
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Abstract

Tungsten ditelluride (WTe$_2$) exhibits extremely large and unsaturated magnetoresistance (MR). Due to the large spatially extensions of Te-5p and W-5d orbitals, the electronic properties of WTe$_2$ are sensitive to the lattice structures, which can probably affect the strongly temperature dependent MR found in experiment. Based on first-principle calculations, we investigate the temperature effect on the lattice and electronic structures of WTe$_2$. Our numerical results show that the thermal expansion coefficients of WTe$_2$ are highly anisotropic and considerably large. However, the temperature (less than 300 K) has ignorable effect on the Fermi surface of WTe$_2$. Our theoretical results clarify that the thermal expansion is not the main reason of the temperature-induced rapid decrease of magnetoresistance.

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Gang Liu, Huimei Liu, Jian Zhou, Xiangang Wan. 2016-09-13. Temperature effect on lattice and electronic structures of WTe$_2$ from first-principles study. https://doi.org/10.1063/1.4974946

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