【摘要】 用优化的MBE参数生长了 1.3μm发光的InAs/GaAs量子点材料 ,并制成发光二极管 ,对不同温度和有源区长度下样品的电致发光谱进行了细致的研究。观察到两个明显的电致发光峰 ,分别对应于量子点基态和激发态的辐射复合发光。实验表明 ,由于能态填充效应的影响 ,适当增大量子点发光器件有源区长度 ,更有利于获得基态的光发射。这个结果提供了一种控制和调节InAs/GaAs量子点发光二极管和激光器的工作波长的方法。更多还原

【Abstract】 Quantum dots (QDs) have attracted much attention in recent years.Many efforts have been devoted to the research of In(Ga)As QDs emitting at 1.3μm and QD-based optoelectronic devices for their technologically important applications.In this paper,light emitting diodes (LEDs) emitting at 1.3μm are fabricated using MBE grown InAs/GaAs QDs,and the EL spectra of QD samples are studied.In the EL spectra,two obvious peaks are observed.They correspond to the ground state emission and the excited state emission respectively.For LEDs with short active region length,the intensity of ground state emission tends to saturate and the intensity of excited state emission increases rapidly with the increase of injection current.For LEDs with long active region length,it remains to be ground state emission with the increase of injection current.The experimental phenomena can be explained by state filling effect.This work has demonstrated a way to control and tune the emitting wavelength of QD-based LEDs and lasers.更多还原