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arXiv · 1302.5891

Effect of anisotropic band curvature on carrier multiplication in graphene

D. M. Basko
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Abstract

We study relaxation of an excited electron in the conduction band of intrinsic graphene at zero temperature due to production of interband electron-hole pairs. The electronic band curvature, being anisotropic because of trigonal warping, is shown to suppress relaxation for a range of directions of the initial electron momentum. For other directions, relaxation is allowed only if the curvature exceeds a finite critical value; otherwise, a non-decaying quasiparticle state is found to exist.

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D. M. Basko. 2013-02-24. Effect of anisotropic band curvature on carrier multiplication in graphene. https://doi.org/10.1103/physrevb.87.165437

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