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arXiv · 2212.12128

Thickness dependent charge density wave networks on thin 1T-TaS$_2$

Wooin Yang·Dowook Kim·Hyoung Kug Kim·Tae-Hwan Kim
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Abstract

We investigate mechanically exfoliated thin 1T-TaS$_2$ with scanning tunneling microscopy at room temperature. Sample preparation without air exposure enables access to intrinsic charge-density-wave (CDW) phases of thin 1T-TaS$_2$. At room temperature, we can observe the expected nearly commensurate CDW (NCCDW) phase on thin flakes similar to bulk 1T-TaS$_2$. Further analysis reveals that the CDW domains in the NCCDW phase become smaller and have more anisotropic shape with decreasing thickness in the range of 8-28 layers. Our findings demonstrate that the anisotropic CDW nature of thin 1T-TaS$_2$ would be crucial to understand its exotic CDW-related phenomena and demand a systematic study on its correlation between the thickness-driven CDW domain anisotropy and the intermediate CDW states in thin 1T-TaS$_2$.

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Wooin Yang, Dowook Kim, Hyoung Kug Kim, Tae-Hwan Kim. 2022-12-23. Thickness dependent charge density wave networks on thin 1T-TaS$_2$. https://doi.org/10.1007/s40042-023-00704-1

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