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arXiv · 0712.1879

Ultrafast Electron-Phonon Decoupling in Graphite

Kunie Ishioka·Muneaki Hase·Masahiro Kitajima·Ludger Wirtz·Angel Rubio·Hrvoje Petek
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Abstract

We report the ultrafast dynamics of the 47.4 THz coherent phonons of graphite interacting with a photoinduced non-equilibrium electron-hole plasma. Unlike conventional materials, upon photoexcitation the phonon frequency of graphite upshifts, and within a few picoseconds relaxes to the stationary value. Our first-principles density functional calculations demonstrate that the phonon stiffening stems from the light-induced decoupling of the non-adiabatic electron-phonon interaction by creating the non-equilibrium electron-hole plasma. Time-resolved vibrational spectroscopy provides a window on the ultrafast non-equilibrium electron dynamics.

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Kunie Ishioka, Muneaki Hase, Masahiro Kitajima, Ludger Wirtz, Angel Rubio, Hrvoje Petek. 2007-12-12. Ultrafast Electron-Phonon Decoupling in Graphite. https://doi.org/10.1103/physrevb.77.121402

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