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Photoluminescence Spectroscopy of Band Gap Shrinkage in GaN

Niladri Sarkar·Subhasis Ghosh
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Abstract

We present an experimental investigation of band-gap shrinkage in n-type GaN using photoluminescence spectroscopy, as a function of electron concentration and temperature. The observed systematic shift of the band-to-band transition energy to lower energies with increasing electron concentration has been interpreted as many-body effects due to exchange and correlation among majority and minority carriers. The band-to-band transition energy also shifts to lower energy with increasing temperature. The parameters that describe the temperature dependence red-shift of the band-edge transition energy are evaluated using different models and we find that the semi-empirical relation based on phonon-dispersion related spectral function leads to excellent fit to the experimental data.

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Niladri Sarkar, Subhasis Ghosh. 2006-04-08. Photoluminescence Spectroscopy of Band Gap Shrinkage in GaN. https://arxiv.org/abs/cond-mat/0604221

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