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arXiv · 0708.4259

Phonon anharmonicities in graphite and graphene

Nicola Bonini·Michele Lazzeri·Nicola Marzari·Francesco Mauri
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Abstract

We determine from first-principles the finite-temperature properties--linewidths, line shifts, and lifetimes--of the key vibrational modes that dominate inelastic losses in graphitic materials. In graphite, the phonon linewidth of the Raman-active E2g mode is found to decrease with temperature; such anomalous behavior is driven entirely by electron-phonon interactions, and does not appear in the nearly-degenerate infrared-active E1u mode. In graphene, the phonon anharmonic lifetimes and decay channels of the A'1 mode at K dominate over E2g at G and couple strongly with acoustic phonons, highlighting how ballistic transport in carbon-based interconnects requires careful engineering of phonon decays and thermalization.

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Nicola Bonini, Michele Lazzeri, Nicola Marzari, Francesco Mauri. 2007-10-25. Phonon anharmonicities in graphite and graphene. https://doi.org/10.1103/physrevlett.99.176802

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