Time-resolved Raman spectroscopy has been applied to probe the anharmonic coupling and electron-phonon interaction of optical phonons in graphite. From the decay of the transient anti-Stokes scattering of the G -mode following ultrafast excitation, we measured a lifetime of 2.2±0.1 ps for zone-center optical phonons. We also observed a transient stiffening of G -mode phonons, an effect attributed to the reduction of the electron-phonon coupling for high electronic temperatures.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Sep 17 2009|