TY - JOUR
T1 - Exciton localization and the Stokes' shift in undoped InGaN/GaN multiquantum wells
AU - Chen, Y. F.
AU - Lin, T. Y.
AU - Yang, H. C.
PY - 2000
Y1 - 2000
N2 - Optical properties of undoped InGaN/GaN multiquantum wells (MQWs) have been investigated by photoconductivity, photoluminescence, and photoluminescence excitation measurements. We report the first observation of persistent photoconductivity (PPC) in InGaN/GaN MQWs and show that the PPC effect arises from In composition fluctuations in the InGaN well layer. From the analysis of the decay kinetics, the localization depth caused by composition fluctuations has been determined. Compared with the results of complementary absorption and photoluminescence measurements, it is found that the quantum-confined Stark effect due to piezoelectric field and composition fluctuations both exist in the InGaN/GaN MQWs. These two effects are responsible for the photoluminescence Stokes' shift in the InGaN well layers. Here, we provide an unique way to distinguish the individual contribution to the Stokes' shift for the piezoelectric field and composition fluctuations.
AB - Optical properties of undoped InGaN/GaN multiquantum wells (MQWs) have been investigated by photoconductivity, photoluminescence, and photoluminescence excitation measurements. We report the first observation of persistent photoconductivity (PPC) in InGaN/GaN MQWs and show that the PPC effect arises from In composition fluctuations in the InGaN well layer. From the analysis of the decay kinetics, the localization depth caused by composition fluctuations has been determined. Compared with the results of complementary absorption and photoluminescence measurements, it is found that the quantum-confined Stark effect due to piezoelectric field and composition fluctuations both exist in the InGaN/GaN MQWs. These two effects are responsible for the photoluminescence Stokes' shift in the InGaN well layers. Here, we provide an unique way to distinguish the individual contribution to the Stokes' shift for the piezoelectric field and composition fluctuations.
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M3 - Conference article
AN - SCOPUS:0033746895
SN - 0277-786X
VL - 3938
SP - 137
EP - 142
JO - Proceedings of SPIE - The International Society for Optical Engineering
JF - Proceedings of SPIE - The International Society for Optical Engineering
T2 - Light-Emitting Diodes: Research, Manufacturing, and Applications IV
Y2 - 26 January 2000 through 27 January 2000
ER -