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.
@article{arxiv.1912.09272,
title = {Giant renormalization of correlation strength in 1T-TaS2 by lattice vibration},
author = {Li Cheng and Shunhong Zhang and Shuang Qiao and Xiaofeng Wang and Lizhao Liu and Zheng Liu},
journal= {arXiv preprint arXiv:1912.09272},
year = {2020}
}
Comments
This submission is a duplicate of the updated version of 1908.04455