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arXiv · 1810.00214

Interaction Driven Quantum Hall Wedding cake-like Structures in Graphene Quantum Dots

Christopher Gutiérrez·Daniel Walkup·Fereshte Ghahari·Cyprian Lewandowski·Joaquin F. Rodriguez-Nieva·Kenji Watanabe·Takashi Taniguchi·Leonid S. Levitov·Nikolai B. Zhitenev·Joseph A. Stroscio
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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 table-top prototype of strongly confined relativistic matter. Here, through a detailed spectroscopic mapping, we provide a spatial visualization of the interplay between spatial and magnetic confinement in a circular graphene resonator. We directly observe the development of a multi-tiered "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 behaviour of quantum-relativistic matter under extreme conditions.

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Christopher Gutiérrez, Daniel Walkup, Fereshte Ghahari, Cyprian Lewandowski, Joaquin F. Rodriguez-Nieva, Kenji Watanabe, Takashi Taniguchi, Leonid S. Levitov, Nikolai B. Zhitenev, Joseph A. Stroscio. 2018-09-29. Interaction Driven Quantum Hall Wedding cake-like Structures in Graphene Quantum Dots. https://doi.org/10.1126/science.aar2014

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