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arXiv · 2010.03915

The effect of ion irradiation on dephasing of coherent optical phonons in GaP

Takuto Ichikawa·Yuta Saito·Muneaki Hase
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Abstract

The dephasing of coherent longitudinal optical (LO) phonons in ion-irradiated GaP has been investigated with a femtosecond pump-probe technique based on electro-optic sampling. The dephasing time of the coherent LO phonon is found to be dramatically prolonged by the introduction of a small amount of defects by means of Ga-ion irradiation. The maximum dephasing time observed at room temperature is 9.1 ps at a Ga$^{+}$ ion dose of 10$^{13}$/cm$^{2}$, which is significantly longer than the value of 8.3 ps for GaP before ion irradiation. The longer dephasing time is explained in terms of the suppression of electron-LO-phonon scattering by the presence of defect-induced deep levels.

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Takuto Ichikawa, Yuta Saito, Muneaki Hase. 2020-10-08. The effect of ion irradiation on dephasing of coherent optical phonons in GaP. https://doi.org/10.1063/5.0020810

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