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arXiv · 0806.0436

Ballistic Hot Electron Transport in Graphene

Wang-Kong Tse·E. H. Hwang·S. Das Sarma
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Abstract

We theoretically study the inelastic scattering rate and the carrier mean free path for energetic hot electrons in graphene, including both electron-electron and electron-phonon interactions. Taking account of optical phonon emission and electron-electron scattering, we find that the inelastic scattering time $τ\sim 10^{-2}-10^{-1} \mathrm{ps}$ and the mean free path $l \sim 10-10^2 \mathrm{nm}$ for electron densities $n = 10^{12}-10^{13} \mathrm{cm}^{-2}$. In particular, we find that the mean free path exhibits a finite jump at the phonon energy $200 \mathrm{meV}$ due to electron-phonon interaction. Our results are directly applicable to device structures where ballistic transport is relevant with inelastic scattering dominating over elastic scattering.

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Wang-Kong Tse, E. H. Hwang, S. Das Sarma. 2008-06-03. Ballistic Hot Electron Transport in Graphene. https://doi.org/10.1063/1.2956669

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