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arXiv · 2107.14524

Optical absorption and carrier multiplication at graphene edges in a magnetic field

Friedemann Queisser·Sascha Lang·Ralf Schützhold
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Abstract

We study optical absorption at graphene edges in a transversal magnetic field. The magnetic field bends the trajectories of particle- and hole excitations into antipodal direction which generates a directed current. We find a rather strong amplification of the edge current by impact ionization processes. More concretely, the primary absorption and the subsequent carrier multiplication is analyzed for a graphene fold and a zigzag edge. We identify exact and approximate selection rules and discuss the dependence of the decay rates on the initial state.

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Friedemann Queisser, Sascha Lang, Ralf Schützhold. 2021-07-30. Optical absorption and carrier multiplication at graphene edges in a magnetic field. https://arxiv.org/abs/2107.14524

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