PLASMA-HEATING IN HIGHLY EXCITED GAN ALGAN MULTIPLE-QUANTUM WELLS/

Time-resolved photoluminescence (PL) spectroscopy was used to investig ate carrier distributions in a GaN/AlGaN multiple quantum well (MQW) s ample under high excitation intensities necessary to achieve lasing th reshold. Room temperature PL spectra showed optical transitions involv ing both confined and unconfined states in the quantum well structure. Analysis of the experimental results using a microscopic theory, indi cates that at high excitation the carrier distributions are characteri zed by plasma temperatures which are significantly higher than the lat tice temperature. The implications of our findings on GaN MQW laser de sign are also discussed. (C) 1998 American Institute of Physics. [S000 3-6951(98)03243-4].