人工晶体学报, 2023, 52 (1): 73, 网络出版: 2023-03-18
引入Si掺杂层调控InGaAs/GaAs表面量子点的光学特性
Optical Properties of InGaAs/GaAs Surface Quantum Dots Regulated by Introducing a Si Doped Interlayer
InGaAs量子点 Si掺杂 表面费米能级 荧光发光谱 间接跃迁辐射 时间分辨荧光光谱 InGaAs quantum dot Si doping surface Fermi level photoluminescence indirect-transition emission time-resolved photoluminescence
摘要
在InGaAs/GaAs表面量子点(SQDs)的GaAs势垒层中引入Si掺杂层,以研究Si掺杂对InGaAs/GaAs SQDs光学特性的影响。荧光发光谱(PL)测量结果显示,InGaAs/GaAs SQDs的发光强烈依赖于Si掺杂浓度。随着掺杂浓度的增加, SQDs的PL峰值位置先红移后蓝移; PL峰值能量与激光激发强度的立方根依赖关系由线性向非线性转变;通过组态交互作用方法发现SQDs的PL峰位蓝移减弱;时间分辨荧光光谱显示了从非线性衰减到线性衰减的转变。以上结果说明Si掺杂能够填充InGaAs SQDs的表面态,并且改变表面费米能级钉扎效应和SQDs的荧光辐射特性。本研究为深入理解与InGaAs SQDs的表面敏感特性关联的物理机制和载流子动力学过程,以及扩大InGaAs/GaAs SQDs传感器的应用提供了实验依据。
Abstract
A Si doped interlayer was introduced into the GaAs barrier layer to study optical properties of InGaAs/GaAs surface quantum dots (SQDs). Photoluminescence (PL) measurements show that luminescence of InGaAs/GaAs SQDs is strongly dependent on Si doping concentration. With increasing the Si doping concentration, InGaAs/GaAs SQDs show clearly different luminescence characteristics, including: PL peak position of SQDs shifts to red at first and then to blue; the dependence of PL peak energy on the cubic root of excitation intensity changes from linear to nonlinear; configuration interaction method shows reduced blue shift for PL band; time-resolved PL indicates a transition from nonlinear decay of type-II QDs to linear decay of type-I QDs. These experimental results indicate that Si doping fill the surface states and modify the surface Fermi level pinning effect, thus changing the luminescence characteristics of InGaAs/GaAs SQDs. This research provides a support for understanding and tailing the surface-sensitive characteristics of InGaAs SQDs for development of sensors.
刘晓辉, 刘景涛, 郭颖楠, 王颖, 郭庆林, 梁宝来, 王淑芳, 傅广生. 引入Si掺杂层调控InGaAs/GaAs表面量子点的光学特性[J]. 人工晶体学报, 2023, 52(1): 73. LIU Xiaohui, LIU Jingtao, GUO Yingnan, WANG Ying, GUO Qinglin, LIANG Baolai, WANG Shufang, FU Guangsheng. Optical Properties of InGaAs/GaAs Surface Quantum Dots Regulated by Introducing a Si Doped Interlayer[J]. Journal of Synthetic Crystals, 2023, 52(1): 73.