THz-bandwidth coherent phonon emission by supported monolayer graphene in the out-of-plane direction

I. Ju Chen, Pierre Adrien Mante, Cheng Kai Chang, Chun Chiang Kuo, Kuei Hsien Chen, Vitalyi Gusev, Chi Kuang Sun

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review


In this report, it is demonstrated that the generation of THz band-width longitudinal coherent acoustic phonons (CAPs) that propagate perpendicularly to graphene's basal plane can be achieved by photo-excitation of supported monolayer graphene. Through exclusively exciting graphene with femtosecond lasers, the observation of backward Brillouin oscillations showed that after graphene absorbed the 800nm light, longitudinal CAPs with momentum in the out-of-plane direction were generated. With the assist of a piezoelectric InGaN quantum well buried inside a wurtzite GaN substrate, the full spectrum of the CAPs was revealed. Experimental results showed that the longitudinal CAP pulse had a bipolar shape and its spectrum had reached up to 1THz. In attempt to understand the generation mechanism of the longitudinal CAP pulse, we proposed a hypothesis based on graphene's carrier dynamics.

Original languageEnglish
Title of host publicationPHONONS 2012 - XIV International Conference on Phonon Scattering in Condensed Matter
Number of pages5
Publication statusPublished - 1 Dec 2012
Externally publishedYes
Event14th International Conference on Phonon Scattering in Condensed Matter, PHONONS 2012 - Ann Arbor, MI, United States
Duration: 8 Jul 201212 Jul 2012

Publication series

NameAIP Conference Proceedings
ISSN (Print)0094-243X
ISSN (Electronic)1551-7616


Conference14th International Conference on Phonon Scattering in Condensed Matter, PHONONS 2012
Country/TerritoryUnited States
CityAnn Arbor, MI


  • backward Brillouin oscillation
  • graphene
  • longitudinal coherent acoustic phonon

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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