Dualistic insulator states in 1T-TaS2 crystals

Yihao Wang; Zhihao 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; Wenjian Lu; Zhe Sun; Hai Xu; Yimin Xiong; Liang Cao

doi:10.1038/s41467-024-47728-0

Dualistic insulator states in 1T-TaS₂ crystals

Nat Commun. 2024 Apr 23;15(1):3425. doi: 10.1038/s41467-024-47728-0.

Authors

Yihao Wang^#¹, Zhihao Li^#^{1

2}, Xuan Luo³, Jingjing Gao³, Yuyan Han¹, Jialiang Jiang¹, Jin Tang⁴, Huanxin Ju⁵, Tongrui Li⁶, Run Lv^{3

7}, Shengtao Cui⁶, Yingguo Yang⁸, Yuping Sun^{1

3

9}, Junfa Zhu⁶, Xingyu Gao¹⁰, Wenjian Lu¹¹, Zhe Sun^{12

13

14}, Hai Xu^{15

16}, Yimin Xiong^{17

18}, Liang Cao¹⁹

Affiliations

¹ Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, 230031, P. R. China.
² Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, Jilin, 130033, P. R. China.
³ Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei, 230031, P. R. China.
⁴ Department of Physics, School of Physics and Optoelectronics Engineering, Anhui University, Hefei, 230601, P. R. China.
⁵ PHI Analytical Laboratory, ULVAC-PHI Instruments Co., Ltd., Nanjing, 211110, Jiangsu, P. R. China.
⁶ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, P. R. China.
⁷ Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, 230026, P. R. China.
⁸ State Key Laboratory of Photovoltaic Science and Technology, School of Microelectronics, Fudan University, Shanghai, 200433, P. R. China.
⁹ Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China.
¹⁰ Shanghai Synchrotron Radiation Facility (SSRF), Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 239 Zhangheng Road, Shanghai, 201204, P. R. China.
¹¹ Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei, 230031, P. R. China. wjlu@issp.ac.cn.
¹² National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, P. R. China. zsun@ustc.edu.cn.
¹³ Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China. zsun@ustc.edu.cn.
¹⁴ Hefei National Laboratory, Hefei, 230028, P. R. China. zsun@ustc.edu.cn.
¹⁵ Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, Jilin, 130033, P. R. China. xuhai@ciomp.ac.cn.
¹⁶ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China. xuhai@ciomp.ac.cn.
¹⁷ Department of Physics, School of Physics and Optoelectronics Engineering, Anhui University, Hefei, 230601, P. R. China. yxiong@ahu.edu.cn.
¹⁸ Hefei National Laboratory, Hefei, 230028, P. R. China. yxiong@ahu.edu.cn.
¹⁹ Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, 230031, P. R. China. lcao@hmfl.ac.cn.

^# Contributed equally.

Abstract

While the monolayer sheet is well-established as a Mott-insulator with a finite energy gap, the insulating nature of bulk 1T-TaS₂ 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-TaS₂ 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-TaS₂ 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.