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arXiv · 1801.08463

Symmetry-breaking supercollisions in Landau-quantized graphene

Florian Wendler·Martin Mittendorff·Jacob C. König-Otto·Samuel Brem·Claire Berger·Walter A. de Heer·Roman Böttger·Harald Schneider·Manfred Helm·Stephan Winnerl·Ermin Malic
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Abstract

Recent pump-probe experiments performed on graphene in a perpendicular magnetic field have revealed carrier relaxation times ranging from picoseconds to nanoseconds depending on the quality of the sample. To explain this surprising behavior, we propose a novel symmetry-breaking defect-assisted relaxation channel. This enables scattering of electrons with single out-of-plane phonons, which drastically accelerate the carrier scattering time in low-quality samples. The gained insights provide a strategy for tuning the carrier relaxation time in graphene and related materials by orders of magnitude.

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Florian Wendler, Martin Mittendorff, Jacob C. König-Otto, Samuel Brem, Claire Berger, Walter A. de Heer, Roman Böttger, Harald Schneider, Manfred Helm, Stephan Winnerl, Ermin Malic. 2018-01-25. Symmetry-breaking supercollisions in Landau-quantized graphene. https://doi.org/10.1103/physrevlett.119.067405

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