Anomalous Temperature Dependence of Photoluminescence in GaInNAs/GaAs Multiple Quantum Wells
LIANG Xiao-Gan1, JIANG De-Sheng1, BIAN Li-Feng1, PAN Zhong2, LI Lian-He2, WU Rong-Han2
1National Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083
2State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083
Anomalous Temperature Dependence of Photoluminescence in GaInNAs/GaAs Multiple Quantum Wells
1National Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083
2State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083
Abstract: Photoluminescence (PL) spectra of GaInNAs/GaAs multiple quantum wells (MQWs) grown on a GaAs substrate by molecular beam epitaxy are measured in a range of temperature and excitation power densities. The energy position of dominant PL peak shows an anomalous S-shape temperature dependence instead of the Varshni relation. By the careful inspection, especially for the PL under lower excitation power density, two near band-edge peaks are well identified. They are assigned to carriers localized in nitrogen-induced bound states and interband excitonic recombinations respectively. It is suggested that the temperature-induced switch of such two luminescence peaks in relative intensity causes a significant mechanism responsible for the S-shape shift observed in GaInNAs. A quantitative model based on the thermal depopulation of carriers is used to explain the temperature dependence of the PL peak related to N-induced bound states.