Dualistic insulator states in 1T-TaS2 crystals
Yihao Wang, Zhi-Hao Li, Xuan Luo, Jingjing Gao, Yuyan Han, Jialiang Jiang, Jin Tang, Huanxin Ju, Tongrui Li, Run Lv, Shengtao Cui, Yingguo Yang, Yuping Sun, Junfa Zhu, Xingyu Gao, W. J. Lu, Zhe Sun, Hai Xu, Yimin Xiong, Liang Cao
Abstract
Abstract While the monolayer sheet is well-established as a Mott-insulator with a finite energy gap, the insulating nature of bulk 1T-TaS 2 crystals remains ambiguous due to their varying dimensionalities and alterable interlayer coupling. In this study, we present a unique approach to unlock the intertwined two-dimensional Mott-insulator and three-dimensional band-insulator states in bulk 1T-TaS 2 crystals by structuring a laddering stack along the out-of-plane direction. Through modulating the interlayer coupling, the insulating nature can be switched between band-insulator and Mott-insulator mechanisms. Our findings demonstrate the duality of insulating nature in 1T-TaS 2 crystals. By manipulating the translational degree of freedom in layered crystals, our discovery presents a promising strategy for exploring fascinating physics, independent of their dimensionality, thereby offering a “three-dimensional” control for the era of slidetronics.