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Band gap renormalization in photoexcited semiconductor quantum wire structures in the GW approximation

E. H. Hwang·S. Das Sarma
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Abstract

We investigate the dynamical self-energy corrections of the electron-hole plasma due to electron-electron and electron-phonon interactions at the band edges of a quasi-one dimensional (1D) photoexcited electron-hole plasma. The leading-order $GW$ dynamical screening approximation is used in the calculation by treating electron-electron Coulomb interaction and electron-optical phonon Fröhlich interaction on an equal footing. We calculate the exchange-correlation induced band gap renormalization (BGR) as a function of the electron-hole plasma density and the quantum wire width. The calculated BGR shows good agreement with existing experimental results, and the BGR normalized by the effective quasi-1D excitonic Rydberg exhibits an approximate one-parameter universality.

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E. H. Hwang, S. Das Sarma. 1998-02-09. Band gap renormalization in photoexcited semiconductor quantum wire structures in the GW approximation. https://doi.org/10.1103/physrevb.58.r1738

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