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arXiv · 1302.0544

Surface polar optical phonon interaction induced many-body effects and hot-electron relaxation in graphene

E. H. Hwang·S. Das Sarma
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Abstract

We theoretically study various aspects of the electron-surface optical phonon interaction effects in graphene on a substrate made of polar materials. We calculate the electron self-energy in the presence of the surface phonon-mediated electron-electron interaction focusing on how the linear chiral graphene dispersion is renormalized by the surface phonons. The electron self-energy as well as the quasiparticle spectral function in graphene are calculated, taking into account electron-polar optical phonon interaction by using a many body perturbative formalism. The scattering rate of free electrons due to polar interaction with surface optical phonons in a dielectric substrate is calculated as a function of the electron energy, temperatures, and carrier density. Effects of screening on the self-energy and scattering rate are discussed. Our theory provides a comprehensive quantitative (and qualitative) picture for surface phonon interaction induced many-body effects and hot electron relaxation in Dirac materials.

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E. H. Hwang, S. Das Sarma. 2013-02-03. Surface polar optical phonon interaction induced many-body effects and hot-electron relaxation in graphene. https://doi.org/10.1103/physrevb.87.115432

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