Defect-limited carrier diffusion in In0.53Ga0.47As-InP single quantum well

The diffusion of electron-hole plasma in an intrinsic In0.53Ga0.47As single quantum well (SQW) was investigated by measurements of the PL intensity pr ofile around the illuminated area. We found that the carrier diffusion leng th increases with the temperature, from 85 to 300 K, according to a defect- limited carrier diffusion. A change in the carrier expansion is observed at about 200 K, which appears to be correlated with the thermal activation of a defect center with activation energy of 120 meV. An Arrhenius function o f the PL emission intensity confirms that a nonradiative recombination chan nel becomes visible with an energy of about 120 meV. (C) 1999 Elsevier Scie nce B.V. All rights reserved.