Interaction-driven quantum Hall wedding cake-like structures in graphene quantum dots
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.
Source: ScienceNOW - Category: Science Authors: Gutierrez, C., Walkup, D., Ghahari, F., Lewandowski, C., Rodriguez-Nieva, J. F., Watanabe, K., Taniguchi, T., Levitov, L. S., Zhitenev, N. B., Stroscio, J. A. Tags: Materials Science, Physics reports Source Type: news