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arXiv · 2007.06469

Nanoscale Conductivity Imaging of Correlated Electronic States in WSe2/WS2 Moir\'e Superlattices

Zhaodong Chu·Emma C Regan·Xuejian Ma·Danqing Wang·Zifan Xu·M. Iqbal Bakti Utama·Kentaro Yumigeta·Mark Blei·Kenji Watanabe·Takashi Taniguchi·Sefaattin Tongay·Feng Wang·Keji Lai
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Abstract

We report the nanoscale conductivity imaging of correlated electronic states in angle-aligned WSe2/WS2 heterostructures using microwave impedance microscopy. The noncontact microwave probe allows us to observe the Mott insulating state with one hole per moir\'e unit cell that persists for temperatures up to 150 K, consistent with other characterization techniques. In addition, we identify for the first time a Mott insulating state at one electron per moir\'e unit cell. Appreciable inhomogeneity of the correlated states is directly visualized in the hetero-bilayer region, indicative of local disorders in the moir\'e superlattice potential or electrostatic doping. Our work provides important insights on 2D moir\'e systems down to the microscopic level.

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Zhaodong Chu, Emma C Regan, Xuejian Ma, Danqing Wang, Zifan Xu, M. Iqbal Bakti Utama, Kentaro Yumigeta, Mark Blei, Kenji Watanabe, Takashi Taniguchi, Sefaattin Tongay, Feng Wang, Keji Lai. 2020-07-13. Nanoscale Conductivity Imaging of Correlated Electronic States in WSe2/WS2 Moir\'e Superlattices. https://doi.org/10.1103/physrevlett.125.186803

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