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arXiv · 1004.3757

Quantum quench dynamics and population inversion in bilayer graphene

Balázs Dóra·Eduardo V. Castro·Roderich Moessner
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Abstract

The gap in bilayer graphene (BLG) can directly be controlled by a perpendicular electric field. By tuning the field through zero at a finite rate in neutral BLG, excited states are produced. Due to screening, the resulting dynamics is determined by coupled non-linear Landau-Zener models. The generated defect density agrees with Kibble-Zurek theory in the presence of subleading logarithmic corrections. After the quench, population inversion occurs for wavevectors close to the Dirac point. This could, at least in principle provide a coherent source of infra-red radiation with tunable spectral properties (frequency and broadening). Cold atoms with quadratic band crossing exhibit the same dynamics.

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Balázs Dóra, Eduardo V. Castro, Roderich Moessner. 2010-09-24. Quantum quench dynamics and population inversion in bilayer graphene. https://doi.org/10.1103/physrevb.82.125441

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