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Interaction-driven quantum Hall wedding cake-like structures in graphene quantum dots.

ABSTRACT: Quantum-relativistic matter is ubiquitous in nature; however, it is notoriously difficult to probe. The ease with which external electric and magnetic fields can be introduced in graphene opens a door to creating a tabletop prototype of strongly confined relativistic matter. Here, through a detailed spectroscopic mapping, we directly visualize the interplay between spatial and magnetic confinement in a circular graphene resonator as atomic-like shell states condense into Landau levels. We directly observe the development of a "wedding cake"-like structure of concentric regions of compressible-incompressible quantum Hall states, a signature of electron interactions in the system. Solid-state experiments can, therefore, yield insights into the behavior of quantum-relativistic matter under extreme conditions.

SUBMITTER: Gutierrez C

PROVIDER: S-EPMC6536895 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Interaction-driven quantum Hall wedding cake-like structures in graphene quantum dots.

Gutiérrez Christopher C Walkup Daniel D Ghahari Fereshte F Lewandowski Cyprian C Rodriguez-Nieva Joaquin F JF Watanabe Kenji K Taniguchi Takashi T Levitov Leonid S LS Zhitenev Nikolai B NB Stroscio Joseph A JA

Science (New York, N.Y.) 20180801 6404

Quantum-relativistic matter is ubiquitous in nature; however, it is notoriously difficult to probe. The ease with which external electric and magnetic fields can be introduced in graphene opens a door to creating a tabletop prototype of strongly confined relativistic matter. Here, through a detailed spectroscopic mapping, we directly visualize the interplay between spatial and magnetic confinement in a circular graphene resonator as atomic-like shell states condense into Landau levels. We direct ...[more]

PMID: 30139870

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