Edge channels of broken-symmetry quantum Hall states in graphene visualized by atomic force microscopy
| Autor: | Cory Dean, Yihang Zeng, Takashi Taniguchi, Daniel Walkup, Son T. Le, Kenji Watanabe, Steven R. Blankenship, M. R. Slot, Fereshte Ghahari, Franz J. Giessibl, Johannes Schwenk, Joseph A. Stroscio, Julian Berwanger, Nikolai B. Zhitenev, Sungmin Kim |
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| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Computer Science::Machine Learning
Superlattice Science Quantum Hall FOS: Physical sciences General Physics and Astronomy Zero-point energy Imaging techniques 02 engineering and technology Quantum Hall effect Computer Science::Digital Libraries 01 natural sciences Article General Biochemistry Genetics and Molecular Biology law.invention Condensed Matter - Strongly Correlated Electrons Statistics::Machine Learning law Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences Topological order 010306 general physics Topological matter Physics Condensed Matter - Materials Science Multidisciplinary Condensed Matter - Mesoscale and Nanoscale Physics Strongly Correlated Electrons (cond-mat.str-el) Condensed matter physics Graphene Degenerate energy levels ddc:530 Materials Science (cond-mat.mtrl-sci) General Chemistry Landau quantization 021001 nanoscience & nanotechnology Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 530 Physik Electronic properties and devices Imaging techniques Quantum Hall Topological matter Computer Science::Mathematical Software Electronic properties and devices 0210 nano-technology Ground state |
| Zdroj: | Nature Communications, Vol 12, Iss 1, Pp 1-11 (2021) Nature Communications |
| Popis: | The quantum Hall (QH) effect, a topologically non-trivial quantum phase, expanded the concept of topological order in physics bringing into focus the intimate relation between the “bulk” topology and the edge states. The QH effect in graphene is distinguished by its four-fold degenerate zero energy Landau level (zLL), where the symmetry is broken by electron interactions on top of lattice-scale potentials. However, the broken-symmetry edge states have eluded spatial measurements. In this article, we spatially map the quantum Hall broken-symmetry edge states comprising the graphene zLL at integer filling factors of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\nu }}={{0}},\pm {{1}}$$\end{document}ν=0,±1 across the quantum Hall edge boundary using high-resolution atomic force microscopy (AFM) and show a gapped ground state proceeding from the bulk through to the QH edge boundary. Measurements of the chemical potential resolve the energies of the four-fold degenerate zLL as a function of magnetic field and show the interplay of the moiré superlattice potential of the graphene/boron nitride system and spin/valley symmetry-breaking effects in large magnetic fields. The broken-symmetry edge states that are the hallmark of the quantum Hall effect in graphene have eluded spatial measurements. Here, the authors spatially map the quantum Hall broken-symmetry edge states using atomic force microscopy and show a gapped ground state proceeding from the bulk through to the quantum Hall edge boundary. |
| Databáze: | OpenAIRE |
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