Topologically protected edge states that conduct ballistic transport in a two-dimensional electron gas under strong out-of-plane magnetic field provides a natural explanation for the quantum Hall effect. In the zeroth Landau level of monolayer graphene, strong Coulomb interaction drives spontaneous breaking of spin and valley symmetries, giving rise to rich physics in the quantum Hall edge states. However, local measurements with the ability to image edge states in real space and probe their symmetry breaking patterns are limited due to sample disorder and limited resolution of the probe. Here we present results of scanning tunneling microscopy/spectroscopy measurements on an ultra-clean graphene sample with a gate-defined lateral interface. In this second talk in a series of three presentations, I will show the emergence of symmetry-breaking edge states tuned by gate induced potential which exhibits unexpected spatial configurations. I will show how these configurations can be understood by the energetic competition between edge electrostatic potential and interactions. These results transcend the conventional picture of edge reconstruction and highlight the role of interaction effects on edge state physics.
*ONR, ARO-MURI, NSF-MRSEC, Moore Foundation, and DOE
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Presenters
Haotan Han
Princeton University
Authors
Haotan Han
Princeton University
Jiachen Yu
Princeton University
Kristina G Wolinski
Princeton University
Ruihua Fan
University of California, Berkeley
Tianle Wang
University of California, Berkeley
Amir Shapour Mohammadi
University of California, Berkeley
Princeton University
Liam A Cohen
University of California, Santa Barbara
Kenji Watanabe
National Institute for Materials Science
NIMS
Research Center for Functional Materials, National Institute for Materials Science
Research Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
Research Center for Functional Materials, National Institute of Material Science, Tsukuba, Japan
National Institute of Materials Science
Advanced Materials Laboratory, National Institute for Materials Science
Takashi Taniguchi
National Institute for Materials Science
International Center for Materials Nanoarchitectonics, National Institute for Materials Science
Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
International Center for Materials Nanoarchitectonics, National Institute of Material Science, Tsukuba, Japan
Advanced Materials Laboratory, National Institute for Materials Science
