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arXiv · 1008.2523

Scattering by flexural phonons in suspended graphene under back gate induced strain

Héctor Ochoa·Eduardo V. Castro·M. I. Katsnelson·F. Guinea
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Abstract

We have studied electron scattering by out-of-plane (flexural) phonon modes in doped suspended graphene and its effect on charge transport. In the free-standing case (absence of strain) the flexural branch shows a quadratic dispersion relation, which becomes linear at long wavelength when the sample is under tension due to the rotation symmetry breaking. In the non-strained case, scattering by flexural phonons is the main limitation to electron mobility. This picture changes drastically when strains above $\bar{u}=10^{-4} n(10^{12}\,\text{cm}^{-2})$ are considered. Here we study in particular the case of back gate induced strain, and apply our theoretical findings to recent experiments in suspended graphene.

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Héctor Ochoa, Eduardo V. Castro, M. I. Katsnelson, F. Guinea. 2012-09-13. Scattering by flexural phonons in suspended graphene under back gate induced strain. https://doi.org/10.1016/j.physe.2011.03.017

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