量子点半导体光放大器的速率方程和增益特性  

Rate Equations and Gain Characteristics of Quantum-Dot Semiconductor Optical Amplifiers

作　　者：李瑞刚[1,2] 刘玉敏[1,2] 俞重远[1,2] 冯昊[1,2] 卢文娟[1,2] 徐子欢[1,2] 

机构地区：[1]北京邮电大学光通信与光电子学研究院,北京100876 [2]北京邮电大学信息光子学与光通信教育部重点实验室,北京100876

出　　处：《中国激光》2009年第6期1366-1370,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(60644004);国家973计划(2003CB314901)资助项目

摘　　要：为了深入研究量子点半导体光放大器(QD-SOA)的特性,建立了量子点半导体光放大器子带导带的三能级系统模型。把系统载流子的速率方程与其他文献采用的速率方程进行了对比优化。通过数值计算得到了瞬态解,并得到载流子在放大器各能级态的浓度分布,验证了量子点中能级分立特性。利用电子和空穴各自的占有几率在基态成一定的线性关系,在稳态下对速率方程求解,得出了量子点半导体光放大器相关的增益特性,以及增益特性与基态电子的占有几率之间的关系。结果表明量子点半导体光放大器具有很高的饱和增益和微分增益,较低的阈值电流等特性。说明量子点半导体光放大器具有比其他体材料和量子阱光放大器更加优异的特性。为光放大器的设计提供了有力的理论指导。To investigate the properties of quantum-dot semiconductor optical amplifiers （QD-SOA）, we establish a three-energy-system model in the conduction band of the QD-SOA. Optimize and compare the rate equations with those in references. Temporal solutions and distribution of electronic states derived by numerical calculation certify the discrete nature of the energy levels of the quantum-dot. Using the fact that the occupation probabilities of electrons and holes are linear in the ground state, we solve the rate equations at steady state to obtain the gain characteristics of QD-SOA and its relation to the occupation probabilities of electrons of the ground state. The results show that the QD-SOA has larger saturated optical gain, higher differential gain and lower operation current. The QD-SOA has more merits than the bulk or quantum-well optical amplifiers, which provide the instructions on designing optical amplifiers.

关 键 词：量子点半导体光放大器 速率方程 占有几率 光增益 

分 类 号：O436[机械工程—光学工程]