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arXiv · 0908.0895

The two-dimensional Brillouin zone of uniaxially strained graphene

Marcel Mohr·Konstantinos Papagelis·Janina Maultzsch·Christian Thomsen
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Abstract

We present an in-depth analysis of the electronic and vibrational band structure of uniaxially strained graphene by ab-initio calculations. Depending on the direction and amount of strain, the Fermi crossing moves away from the $K$-point. However, graphene remains semimetallic under small strains. The deformation of the Dirac cone near the $K$-point gives rise to a broadening of the 2D Raman mode. In spite of specific changes in the electronic and vibrational band structure the strain-induced frequency shifts of the Raman active E2g and 2D modes are independent of the direction of strain. Thus, the amount of strain can be directly determined from a single Raman measurement.

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Marcel Mohr, Konstantinos Papagelis, Janina Maultzsch, Christian Thomsen. 2009-08-06. The two-dimensional Brillouin zone of uniaxially strained graphene. https://doi.org/10.1103/physrevb.80.205410

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