Hot carrier cooling by acoustic phonons in epitaxial graphene by ultrafast pump-probe spectroscopy

نویسندگان

  • Dong Sun
  • Charles Divin
  • Claire Berger
  • Theodore B. Norris
چکیده

We report the application nondegenerate ultrafast midinfrared spectroscopy to investigate the acoustic phonon cooling process in epitaxial graphene. We show that the powerdependent experimental results match theoretical predictions of the low temperature acoustic cooling process. The hot phonon effect in acoustic phonon cooling is observed experimentally, and a deformation potential of 30 eV can be determined from fitting the data.

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تاریخ انتشار 2011