Evidence for large configuration-induced bandgap fluctuations in GaAsN alloys
Abstract
We have measured the near bandgap absorption of GaAs_1-xNx thin films with x<0.012. The spectra were analyzed with a model which allows a precise determination of the band gap and of the width of the optical transitions; the latter is found to increase, for x>0.002, well beyond what is expected in a III-V alloy. Ab-initio calculations performed within the generalized gradient approximation reveal that the band gap depends markedly on nitrogen atomic configuration. The anomalous broadening of the intrinsic optical transitions thus gives strong evidence for configuration-induced bandgap fluctuations.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARA11004B