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arXiv · 1101.2490

Control of carrier transport in GaAs by longitudinal-optical phonon-carrier scattering using a pair of laser pump pulses

Muneaki Hase·Daisuke Hayashi·J. D. Lee
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Abstract

We demonstrate optical control of the LO phonon-plasmon coupled (LOPC) modes in GaAs by using a femtosecond pump-pulse pair. The relaxation time of the plasmon-like LOPC mode significantly depends on the separation time (Δt) of the pump-pulse pair. Especially it is maximized when Δt becomes simultaneously comparable to the half period of the longitudinal optical (LO) phonon oscillation and resonant to the 3/4 period of the plasmon-like LOPC oscillation. We attribute these observations to the modification of carrier-LO phonon scattering and ballistic motion of the plasmon-like LOPC mode.

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Muneaki Hase, Daisuke Hayashi, J. D. Lee. 2011-01-31. Control of carrier transport in GaAs by longitudinal-optical phonon-carrier scattering using a pair of laser pump pulses. https://doi.org/10.1063/1.3562188

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