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arXiv · 0908.2831

Electrostatically confined Quantum Rings in bilayer Graphene

M. Zarenia·J. M. Pereira Jr.·F. M. Peeters·G. A. Farias
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Abstract

We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field ($B_{0}$) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a $B_0 \to -B_0$ transformation and, for a fixed total angular momentum index $m$, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anti-crossings, which arise due to the overlap of gate-confined and magnetically-confined states.

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M. Zarenia, J. M. Pereira Jr., F. M. Peeters, G. A. Farias. 2009-08-19. Electrostatically confined Quantum Rings in bilayer Graphene. https://doi.org/10.1021/nl902302m

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