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Temperature dependence of the band gap shrinkage due to electron-phonon interaction in undoped n-type GaN

Niladri Sarkar·Subhasis Ghosh
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Abstract

The photoluminescence spectra of band-edge transitions in GaN is studied as a function of temperature. The parameters that describe the temperature dependence red-shift of the band-edge transition energy and the broadening of emission line are evaluated using different models. We find that the semi-empirical relation based on phonon-dispersion related spectral function leads to excellent fit to the experimental data. The exciton-phonon coupling constants are determined from the analysis of linewidth broadening.

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Niladri Sarkar, Subhasis Ghosh. 2005-03-25. Temperature dependence of the band gap shrinkage due to electron-phonon interaction in undoped n-type GaN. https://doi.org/10.1088/0953-8984%2F18%2F5%2F021

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