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Multi-phonon Raman scattering in semiconductor nanocrystals: importance of non-adiabatic transitions

E. P. Pokatilov·S. N. Klimin·V. M. Fomin·J. T. Devreese·F. W. Wise
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Abstract

Multi-phonon Raman scattering in semiconductor nanocrystals is treated taking into account both adiabatic and non-adiabatic phonon-assisted optical transitions. Because phonons of various symmetries are involved in scattering processes, there is a considerable enhancement of intensities of multi-phonon peaks in nanocrystal Raman spectra. Cases of strong and weak band mixing are considered in detail. In the first case, fundamental scattering takes place via internal electron-hole states and is participated by s- and d-phonons, while in the second case, when the intensity of the one-phonon Raman peak is strongly influenced by the interaction of an electron and of a hole with interface imperfections (e. g., with trapped charge), p-phonons are most active. Calculations of Raman scattering spectra for CdSe and PbS nanocrystals give a good quantitative agreement with recent experimental results.

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E. P. Pokatilov, S. N. Klimin, V. M. Fomin, J. T. Devreese, F. W. Wise. 2001-11-15. Multi-phonon Raman scattering in semiconductor nanocrystals: importance of non-adiabatic transitions. https://doi.org/10.1103/physrevb.65.075316

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