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arXiv · 1301.0799

Theoretical 2D Raman band of strained graphene

Valentin N. Popov·Philippe Lambin
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Abstract

We study the 2D Raman band of in-plane uniaxially strained graphene within a non-orthogonal tight-binding model. At non-zero strain, the obtained 2D band splits into two subbands at strain angles $0^{\circ}$ and $30^{\circ}$ or into three subbands at intermediate angles. The evolution of the 2D subbands is calculated systematically in the range of the accessible strains from -1% to 3% and for the commonly used laser photon energy from 1.5 eV to 3.0 eV. The strain rate and dispersion rate of the 2D subbands are derived and tabulated. In particular, these two quantities show large variations up to 50%. The results on the 2D subbands can be used for detecting and monitoring strain in graphene for nanoelectronics applications.

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Valentin N. Popov, Philippe Lambin. 2013-01-04. Theoretical 2D Raman band of strained graphene. https://doi.org/10.1103/physrevb.87.155425

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