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arXiv · 2102.07915

Semiconductor-metal phase transition and emergent charge density waves in 1T-ZrX$_2$ (X = Se, Te) at the two-dimensional limit

Ming-Qiang Ren·Sha Han·Jia-Qi Fan·Shujing Li·Shu-Ze Wang·Fawei Zheng·Ping Zhang·Xu-Cun Ma·Qi-Kun Xue·Can-Li Song
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Abstract

Charge density wave (CDW) is a collective quantum phenomenon in metals and features a wave-like modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX$_2$ (X = Se, Te) ultra-thin films, accompanied by a commensurate 2 $\times$ 2 CDW order. Furthermore, we observed a CDW energy gap up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX$_2$ films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of Zr 4d-derived elliptical electron conduction band at the corners of the Brillouin zone.

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Ming-Qiang Ren, Sha Han, Jia-Qi Fan, Shujing Li, Shu-Ze Wang, Fawei Zheng, Ping Zhang, Xu-Cun Ma, Qi-Kun Xue, Can-Li Song. 2021-02-16. Semiconductor-metal phase transition and emergent charge density waves in 1T-ZrX$_2$ (X = Se, Te) at the two-dimensional limit. https://doi.org/10.1021/acs.nanolett.1c04372

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