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arXiv · 0903.3275

Quasi-energy spectra of graphene dots under intense ac field: field anisotropy and photon dressed quantum rings

P. H. Rivera·A. L. C. Pereira·P. A. Schulz
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Abstract

A graphene quantum dot under intense ac field and static low magnetic field is investigated. From a tight-binding perspective, applying a Fourier-Floquet transformation and renormalization process, we observe that graphene -intrinsically anisotropic- reveals field polarization signatures in the quasi-density of states. For the ac field polarized along the armchair direction, the dressed electronic structure shows an emergent property: an ac field induced quantum ring. This is inferred by the orientation-dependent formation of a miniband of energy states periodically modulated with increasing magnetic field, exactly analogous to the behavior of a quantum ring spectrum.

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P. H. Rivera, A. L. C. Pereira, P. A. Schulz. 2009-03-19. Quasi-energy spectra of graphene dots under intense ac field: field anisotropy and photon dressed quantum rings. https://doi.org/10.1103/physrevb.79.205406

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