Presentation Information
[8a-N101-9]Carrier Lifetime Estimation in InGaN Quantum Wells by Intensity-Modulated Optical Excitation
〇Soya Yamagishi1, Atsushi.A Yamaguchi1, Shigetaka Tomiya2 (1.Kanazawa Inst.Tech., 2.NAIST)
Keywords:
Nitride semiconductor,Intensity-Modulated Optical Excitation,InGaN Quantum Wells
InGaN is widely used as an active-layer material for light-emitting and laser diodes because it can emit light over a broad visible wavelength range by controlling its alloy composition. However, emission efficiency decreases with increasing wavelength, and the mechanism has not been fully understood. In this study, carrier lifetimes in an InGaN single quantum well were evaluated using an optical intensity modulation excitation method. When the excitation laser intensity is modulated at high frequencies, the photoluminescence (PL) intensity exhibits a reduced modulation depth and a phase delay due to the finite carrier lifetime. By analyzing the frequency dependence of the phase delay with a theoretical model, the carrier lifetime can be determined. Future work will compare these results with those obtained by time-resolved photoluminescence (TRPL) measurements to gain a better understanding of carrier dynamics in InGaN quantum wells.