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arXiv · 1912.09272

Giant renormalization of correlation strength in 1T-TaS2 by lattice vibration

Li Cheng·Shunhong Zhang·Shuang Qiao·Xiaofeng Wang·Lizhao Liu·Zheng Liu
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Abstract

The lattice thermodynamics of a 1T-TaS2 layer, e.g. the spontaneous formation of a sqrt13*sqrt13 commensurate charge density wave (CCDW) and vibrations around the equilibrium position, is calculated by ab initio molecular dynamics. Based on that, we examine how the ground-state electronic structure is renormalized by lattice temperature. We show that the band gap within the density functional theory plus onsite-U correction shrinks by half when the temperature raises from 0 K to 200 K. The gap size reduction is one order of magnitude larger than the temperature variation in energy. This giant temperature dependence is closely related to the CCDW-triggered Mottness in 1T-TaS2, and is expected to result in unconventional thermodynamic properties.

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Li Cheng, Shunhong Zhang, Shuang Qiao, Xiaofeng Wang, Lizhao Liu, Zheng Liu. 2019-12-18. Giant renormalization of correlation strength in 1T-TaS2 by lattice vibration. https://arxiv.org/abs/1912.09272

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