Coherent longitudinal optical phonon and plasmon coupling in GaAs
Journal
Applied Physics Letters
Journal Volume
81
Journal Issue
20
Pages
3771-3773
Date Issued
2002
Author(s)
Chang, N.-A.
Abstract
The coupling between femtosecond laser-excited coherent LO phonons and plasmon in GaAs was investigated in real time via two-pump time-resolved second-harmonic generation. The coherent LO phonon–plasmon coupling mode dominated the lattice oscillation when the photoexcited plasma density exceeded 3×1018/cm3. Its oscillation intensity showed sinusoidal dependence on the separation time between the two pumps and a phase shift from the initial LO phonon oscillation. These observations reveal the formation time of photoexcited plasmon and its coherent coupling with LO phonon in femtosecond time scale.
Publisher
American Institute of Physics
Type
journal article