Open AccessTerahertz pulse induced intervalley scattering in photoexcited GaAs
Author(s) -
Fuhai Su,
F. Blanchard,
Gargi Sharma,
Luca Razzari,
A. Ayesheshim,
Tyler L. Cocker,
Lyubov V. Titova,
T. Ozaki,
J. C. Kieffer,
Roberto Morandotti,
M. Reid,
Frank A. Hegmann
Publication year - 2009
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.009620
Subject(s) - terahertz radiation , picosecond , drude model , scattering , electric field , optics , terahertz spectroscopy and technology , materials science , pulse (music) , optoelectronics , scattering rate , electron , physics , laser , quantum mechanics , detector
Nonlinear transient absorption bleaching of intense few-cycle terahertz (THz) pulses is observed in photoexcited GaAs using opticalpump--THz-probe techniques. A simple model of the electron transport dynamics shows that the observed nonlinear response is due to THz-electric- field-induced intervalley scattering over sub-picosecond time scales as well as an increase in the intravalley scattering rate attributed to carrier heating. Furthermore, the nonlinear nature of the THz pulse transmission at high peak fields leads to a measured terahertz conductivity in the photoexcited GaAs that deviates significantly from the Drude behavior observed at low THz fields, emphasizing the need to explore nonlinear THz pulse interactions with materials in the time domain.