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arXiv · 1110.0212

Many-Electron Effects on Optical Absorption Spectra of Strained Graphene

Yufeng Liang·Shouting Huang·Li Yang
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Abstract

We employ the first-principles GW+Bethe Salpeter equation approach to study the electronic structure and optical absorption spectra of uniaxial strained graphene with many-electron effects included. Applied strain not only induces an anisotropic Fermi velocity but also tilts the axis of the Dirac cone. As a result, the optical response of strained graphene is dramatically changed; the optical absorption is anisotropic, strongly depending on the polarization direction of the incident light and the strain orientation; the characteristic single optical absorption peak from {\pi}-{\pi}* transitions of pristine graphene is split into two peaks and both display enhanced excitonic effects. Within the infrared regime, the optical absorbance of uniaxial strained graphene is no longer a constant because of the broken symmetry and associated anisotropic excitonic effects. Within the visible-light regime, we observe a prominent optical absorption peak due to a significant red shift by electron-hole interactions, enabling us to change the visible color and transparency of stretched graphene. Finally, we also reveal enhanced excitonic effects within the ultraviolet regime (8 to 15 eV), where a few nearly bound excitons are identified.

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Yufeng Liang, Shouting Huang, Li Yang. 2011-10-02. Many-Electron Effects on Optical Absorption Spectra of Strained Graphene. https://doi.org/10.1557/jmr.2011.412

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