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arXiv · 0812.2258

Raman Spectroscopy of Graphene under Uniaxial Stress: Phonon Softening and Determination of the Crystallographic Orientation

Mingyuan Huang·Hugen Yan·Changyao Chen·Daohua Song·Tony F. Heinz·James Hone
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Abstract

We present a systematic study of the Raman spectra of optical phonons in graphene monolayers under tunable uniaxial tensile stress. Both the G and 2D bands exhibit significant red shifts. The G band splits into two distinct sub-bands (G+, G-) because of the strain-induced symmetry breaking. Raman scattering from the G+ and G- bands shows a distinctive polarization dependence that reflects the angle between the axis of the stress and the underlying graphene crystal axes. Polarized Raman spectroscopy therefore constitutes a purely optical method for the determination of the crystallographic orientation of graphene.

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Mingyuan Huang, Hugen Yan, Changyao Chen, Daohua Song, Tony F. Heinz, James Hone. 2008-12-11. Raman Spectroscopy of Graphene under Uniaxial Stress: Phonon Softening and Determination of the Crystallographic Orientation. https://arxiv.org/abs/0812.2258

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