Metal to Mott Insulator Transition in Two-dimensional 1T-TaSe$_2$
Abstract
When electron-electron interaction dominates over other electronic energy scales, exotic, collective phenomena often emerge out of seemingly ordinary matter. The strongly correlated phenomena, such as quantum spin liquid and unconventional superconductivity, represent a major research frontier and a constant source of inspiration. Central to strongly correlated physics is the concept of Mott insulator, from which various other correlated phases derive. The advent of two-dimensional (2D) materials brings unprecedented opportunities to the study of strongly correlated physics in the 2D limit. In particular, the enhanced correlation and extreme tunability of 2D materials enables exploring strongly correlated systems across uncharted parameter space. Here, we discover an intriguing metal to Mott insulator transition in 1T-TaSe as the material is thinned down to atomic thicknesses. Specifically, we discover, for the first time, that the bulk metallicity of 1T-TaSe arises from a band crossing Fermi level. Reducing the dimensionality effectively quenches the kinetic energy of the initially itinerant electrons and drives the material into a Mott insulating state. The dimensionality-driven Metal to Mott insulator transition resolves the long-standing dichotomy between metallic bulk and insulating surface of 1T-TaSe. Our results additionally establish 1T-TaSe as an ideal variable system for exploring various strongly correlated phenomena.
Keywords
Cite
@article{arxiv.2211.08114,
title = {Metal to Mott Insulator Transition in Two-dimensional 1T-TaSe$_2$},
author = {Ning Tian and Zhe Huang and Bo Gyu Jang and Shuaifei Guo and Ya-Jun Yan and Jingjing Gao and Yijun Yu and Jinwoong Hwang and Meixiao Wang and Xuan Luo and Yu Ping Sun and Zhongkai Liu and Dong-Lai Feng and Xianhui Chen and Sung-Kwan Mo and Minjae Kim and Young-Woo Son and Dawei Shen and Wei Ruan and Yuanbo Zhang},
journal= {arXiv preprint arXiv:2211.08114},
year = {2022}
}