Nanoscale Conductivity Imaging of Correlated Electronic States in WSe2/WS2 Moire Superlattices

被引：50

作者：

Chu, Zhaodong ^{[1
]}

Regan, Emma C. ^{[2
,3
,4
]}

Ma, Xuejian ^{[1
]}

Wang, Danqing ^{[2
,3
,4
]}

Xu, Zifan ^{[1
]}

Utama, M. Iqbal Bakti ^{[2
,4
,5
]}

Yumigeta, Kentaro ^{[6
]}

Blei, Mark ^{[6
]}

Watanabe, Kenji ^{[7
]}

Taniguchi, Takashi ^{[8
]}

Tongay, Sefaattin ^{[6
]}

Wang, Feng ^{[2
,4
,9
,10
]}

Lai, Keji ^{[1
]}

机构：

[1] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA

[2] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA

[3] Univ Calif Berkeley, Grad Grp Appl Sci & Technol, Berkeley, CA 94720 USA

[4] Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA

[5] Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA

[6] Arizona State Univ, Sch Engn Matter Transport & Energy, Tempe, AZ 85287 USA

[7] Natl Inst Mat Sci, Res Ctr Funct Mat, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan

[8] Natl Inst Mat Sci, Int Ctr Mat Nanoarchitecton, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan

[9] Univ Calif Berkeley, Kavli Energy NanoSci Inst, Berkeley, CA 94720 USA

[10] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA

来源：

PHYSICAL REVIEW LETTERS | 2020年 / 125卷 / 18期

关键词：

GRAPHENE; INSULATOR; MOTT; INHOMOGENEITY;

D O I：

10.1103/PhysRevLett.125.186803

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

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 moire 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 moire unit cell. Appreciable inhomogeneity of the correlated states is directly visualized in the heterobilayer region, indicative of local disorders in the moire superlattice potential or electrostatic doping. Our work provides important insights on 2D moire systems down to the microscopic level.

引用

页数：6

共 45 条

[1]

[Anonymous], private communication

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Baugher BWH, 2014, NAT NANOTECHNOL, V9, P262, DOI [10.1038/nnano.2014.25, 10.1038/NNANO.2014.25]

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