A critical factor affecting on the performance of blue-violet InGaN multiquantum well laser diodes: Nonradiative centers

Carrier lifetime at room temperature (RT) was measured for blue-violet emitting InGaN multiquantum wells as a function of excitation intensity. The carrier lifetime of a p/n-doped waveguide sample (PNLD) was longer than those of undoped or n-doped waveguide samples. For PNLD, the long decay component became dominant at moderate excitation, in contrast to the others for which the fast decaying component remained dominant. The lifetime behavior of PNLD, in conjunction with its strong photoluminescence intensity, originates from the reduction of nonradiative centers. We conclude that the defect density is an important determinant of the RT performance of blue-violet laser diodes. (C) 2010 American Institute of Physics. [doi:10.1063/1.3481091]