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arXiv · 1310.2683

Optical characterization of electron-phonon interactions at the saddle point in graphene

Adam T. Roberts·Rolf Binder·Nai H. Kwong·Dheeraj Golla·Daniel Cormode·Brian J. LeRoy·Henry O. Everitt·Arvinder Sandhu
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Abstract

The role of electron-phonon interactions is experimentally and theoretically investigated near the saddle point absorption peak of graphene. The differential optical transmission spectra of multiple, non-interacting layers of graphene reveals the dominant role played by electron-acoustic phonon coupling in bandstructure renormalization. Using a Born approximation for electron-phonon coupling and experimental estimates of the dynamic phonon lattice temperature, we deduce the effective acoustic deformation potential to be $D^{\rm ac}_{\rm eff} \simeq 5$eV. This value is in accord with recent theoretical predictions but differs substantially from those obtained using electrical transport measurements.

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Adam T. Roberts, Rolf Binder, Nai H. Kwong, Dheeraj Golla, Daniel Cormode, Brian J. LeRoy, Henry O. Everitt, Arvinder Sandhu. 2013-10-10. Optical characterization of electron-phonon interactions at the saddle point in graphene. https://doi.org/10.1103/physrevlett.112.187401

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