Electron-phonon interaction effects on the direct gap transitions of nanoscale Si films

Vimal K Kamineni; Alain C Diebold

doi:10.1063/1.3650470

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arXiv · 1103.4102

Electron-phonon interaction effects on the direct gap transitions of nanoscale Si films

Vimal K Kamineni·Alain C Diebold

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Abstract

This study shows that the dielectric function of crystalline Si quantum wells (c-Si QW) is influenced by both carrier confinement and electron-phonon interactions. The energy shifts and lifetime broadening of the excitonic E1 direct gap transition of c-Si QWs from 2 to 10 nm are found to have a significant dimensional and temperature dependence that can be traced to changes in the phonon dispersion of nanoscale films. The influence of electron-phonon interactions on the dielectric function was verified by altering the phonon dispersion using different dielectric layers above a 5 nm c-Si QW.

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Vimal K Kamineni, Alain C Diebold. 2011-08-24. Electron-phonon interaction effects on the direct gap transitions of nanoscale Si films. https://doi.org/10.1063/1.3650470

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