Optical transitions and energy relaxation of hot carriers in Si nanocrystals

A. N. Poddubny; A. A. Prokofiev; I. N. Yassievich

doi:10.1063/1.3525375

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arXiv · 1010.0166

Optical transitions and energy relaxation of hot carriers in Si nanocrystals

A. N. Poddubny·A. A. Prokofiev·I. N. Yassievich

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Abstract

Dynamics of hot carriers confined in Si nanocrystals is studied theoretically using atomistic tight binding approach. Radiative, Auger-like and phonon-assisted processes are considered. The Auger-like energy exchange between electrons and holes is found to be the fastest process in the system. However the energy relaxation of hot electron-hole pair is governed by the single optical phonon emission. For a considerable number of states in small nanocrystals single-phonon processes are ruled out by energy conservation law.

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A. N. Poddubny, A. A. Prokofiev, I. N. Yassievich. 2010-10-01. Optical transitions and energy relaxation of hot carriers in Si nanocrystals. https://doi.org/10.1063/1.3525375

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