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arXiv · 2106.10431

Moire Superlattice Modulations in Single-Unit-Cell FeTe Films Grown on NbSe2 Single Crystals

Han-Bin Deng·Yuan Li·Zili Feng·Jian-Yu Guan·Xin Yu1·Xiong Huang·Rui-Zhe Liu·Chang-Jiang Zhu·Limin Liu·Ying-Kai Sun·Xi-liang Peng·Shuai-Shuai Li·Xin Du·Zheng Wang·Rui Wu·Jia-Xin Yin·You-Guo Shi·Han-Qing Mao
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Abstract

Interface can be a fertile ground for exotic quantum states, including topological superconductivity, Majorana mode, fractal quantum Hall effect, unconventional superconductivity, Mott insulator, etc. Here we grow single-unit-cell (1UC) FeTe film on NbSe2 single crystal by molecular beam epitaxy (MBE) and investigate the film in-situ with home-made cryogenic scanning tunneling microscopy (STM) and non-contact atomic force microscopy (AFM) combined system. We find different stripe-like superlattice modulations on grown FeTe film with different misorientation angles with respect to NbSe2 substrate. We show that these stripe-like superlattice modulations can be understood as moire pattern forming between FeTe film and NbSe2 substrate. Our results indicate that the interface between FeTe and NbSe2 is atomically sharp. By STM-AFM combined measurement, we suggest the moire superlattice modulations have an electronic origin when the misorientation angle is relatively small (<= 3 degree) and have structural relaxation when the misorientation angle is relatively large (>= 10 degree).

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Han-Bin Deng, Yuan Li, Zili Feng, Jian-Yu Guan, Xin Yu1, Xiong Huang, Rui-Zhe Liu, Chang-Jiang Zhu, Limin Liu, Ying-Kai Sun, Xi-liang Peng, Shuai-Shuai Li, Xin Du, Zheng Wang, Rui Wu, Jia-Xin Yin, You-Guo Shi, Han-Qing Mao. 2021-06-19. Moire Superlattice Modulations in Single-Unit-Cell FeTe Films Grown on NbSe2 Single Crystals. https://doi.org/10.1088/1674-1056/ac0816

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