Observation of amplified stimulated terahertz emission from optically pumped heteroepitaxial graphene-on-silicon materials

Hiromi Karasawa, Tsuneyoshi Komori, Takayuki Watanabe, Akira Satou, Hirokazu Fukidome, Maki Suemitsu, Victor Ryzhii, Taiichi Otsuji

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

We experimentally observed the fast relaxation and relatively slow recombination dynamics of photogenerated electrons/holes in a heteroepitaxial graphene-on-Si material under pumping with a 1550-nm, 80-fs pulsed fiber laser and probing with the corresponding terahertz beam generated by and synchronized with the pumping laser. The time-resolved electric-nearfield intensity originating from the coherent terahertz photon emission is electrooptically sampled in total-reflection geometry. The Fourier spectrum fairly agrees the product of the negative dynamic conductivity and the expected THz photon spectrum reflecting the pumping photon spectrum. This phenomenon is interpreted as an amplified stimulated terahertz emission.

Original languageEnglish
Pages (from-to)655-665
Number of pages11
JournalJournal of Infrared, Millimeter, and Terahertz Waves
Volume32
Issue number5
DOIs
Publication statusPublished - 2011 May 1

Keywords

  • Coherent
  • GOS
  • Graphene
  • Negative-dynamic conductivity
  • Population inversion
  • Stimulated emission
  • Terahertz

ASJC Scopus subject areas

  • Radiation
  • Instrumentation
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Observation of amplified stimulated terahertz emission from optically pumped heteroepitaxial graphene-on-silicon materials'. Together they form a unique fingerprint.

  • Cite this