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arXiv · 1606.05663

Driven quantum tunneling and pair creation with graphene Landau levels

Denis Gagnon·François Fillion-Gourdeau·Joey Dumont·Catherine Lefebvre·Steve MacLean
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Abstract

Driven tunneling between graphene Landau levels is theoretically linked to the process of pair creation from vacuum, a prediction of quantum electrodynamics (QED). Landau levels are created by the presence of a strong, constant, quantizing magnetic field perpendicular to a graphene mono-layer. Following the formal analogy between QED and the description of low-energy excitations in graphene, solutions of the fully interacting Dirac equation are used to compute electron-hole pair creation driven by a circularly or linearly polarized field. This is achieved via the coupled channel method, a numerical scheme for the solution of the time-dependent Dirac equation in the presence of bound states. The case of a monochromatic driving field is first considered, followed by the more realistic case of a pulsed excitation. We show that the pulse duration yields an experimental control parameter over the maximal pair yield. Orders of magnitude of the pair yield are given for experimentally achievable magnetic fields and laser intensities weak enough to preserve the Landau level structure.

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Denis Gagnon, François Fillion-Gourdeau, Joey Dumont, Catherine Lefebvre, Steve MacLean. 2016-06-17. Driven quantum tunneling and pair creation with graphene Landau levels. https://doi.org/10.1103/physrevb.93.205415

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