Effect of nitrogen fraction on the temperature dependence of GaNAs/GaAs quantum-well emission

The effects of nitrogen fraction on the temperature dependence of GaNxAs1-x/GaAs (x<2.8%) quantum-well emission was investigated using steady-state photoluminescence between 2 and 300 K. At low temperatures, a characteristic S-shape behavior indicative of carrier localization was observed for each of the samples. This is believed to result from the large miscibility gap induced by the nitrogen, which results in structural/compositional fluctuations in the well. In the high temperature regime (T>150 K) where the emission has a linear dependence, a strong reduction in emission temperature dependence was observed with increasing nitrogen. The temperature dependence was modeled using the band anticrossing approach, with the interaction matrix element parameter C-NM (V-MN=-C(MN)root)x and the nitrogen level parameter gamma (E-N=E-N(0)-gammax) used as fitting parameters. (C) 2003 American Institute of Physics.