近800nm波长张应变GaAsP/A1GaAs量子阱激光器有源区的设计  

Design of active region for GaAsP/AlGaAs tensile strain quantum well laser diodes near 800 nm wavelength

作　　者：李建军[1] Li Jian-Jun(Key Laboratory of Opto-electronics Technology （Beijing University of Technology）, Ministry of Education, Beijing 100124, China)

机构地区：[1]北京工业大学,光电子技术教育部重点实验室,北京100124

出　　处：《物理学报》2018年第6期231-243,共13页Acta Physica Sinica

基　　金：光电子技术教育部重点实验室发展基金(批准号:PXM2017_014204_500034);北京市教委能力提升项目(批准号:PXM2016_014204_500026)资助的课题~~

摘　　要：张应变GaAs_(1-x)P_x量子阱是高性能大功率半导体激光器的核心有源区,基于能带结构分析优化其结构参数具有重要的应用指导意义.首先,基于6×6 Luttinger-Kohn模型,采用有限差分法计算了张应变GaAs_(1-x)P_x量子阱的能带结构,得到了第一子带间跃迁波长固定为近800 nm时的阱宽-阱组分关系,即随着阱组分x的增加,需同时增大阱宽,且阱宽较大时靠近价带顶的是轻空穴第一子带lh_1,阱宽较小时靠近价带顶的是重空穴第一子带hh_1.计算并分析了导带第一子带c_1到价带子带lh_1和hh_1的跃迁动量矩阵元.针对808 nm量子阱激光器,模拟计算了阈值增益与阱宽的关系,得到大阱宽有利于横磁模激射,小阱宽有利于横电模激射.进一步考虑了自发辐射和俄歇复合之后,模拟计算了808 nm量子阱激光器的阱宽与阈值电流密度的关系,阱宽较大时载流子对高能级子带的填充使得阈值电流密度增加,而阱宽较小时则是低的有源区光限制因子导致阈值电流密度升高,因此存在一最佳的阱宽-阱组分组合,可使阈值电流密度达到最小.本文的模拟结果可对张应变GaAs_(1-x)P_x量子阱激光器的理论分析和结构设计提供理论指导.As an active region, the tensile strain GaAs1-xPx quantum well plays an important role in the high power semicon- ductor laser diode with a wavelength of about 800 nm. Accompanied with the improved stability due to the Al-free active region, the GaAs1-xPx quantum well laser also shows a high level of catastrophic optical mirror damage because of the non-absorbing window at the facet, which is formed automatically by the relaxation of the tensile strain GaAs1-xPx material. On the other side, the GaAs1-xPx quantum well laser can provide a transverse magnetic （TM） polarized light source which is important for many solid state laser systems. However, the energy band structure of the tensile strain GaAs1-xPx quantum well is more complicated than that of the compressed or lattice matched quantum well. Although the light hole band is on the top of the heavy hole band for the bulk tensile strain GaAs1-xPx material, the situation may be different from the tensile strain GaAs1-xPx quantum well, in which the first light hole subband lhl can be either on the top of the first heavy hole subband hhl or reversed, that will cause the laser to generate either TM or transverse electric （TE） polarized light according to the well structure. So it is meaningful to optimize the tensile strain GaAs1-xPx quantum well structure based on the analysis of the energy band structure. Firstly, according to the 6×6 Luttinger-Kohn theory, the energy band structure of the tensile strain GaAs1-xPx quantum well is calculated by the finite difference method. The relationship between the interband transition energy and the well structure parameters is established. It is found that the well composition x and the well width should increase simultaneously, in order to fix the first subband transition wavelength at about 800 nm. Special attention is paid to the 808 nm quantum well, the valence structures of different well widths are calculated, the detailed analysis of the envelope function shows that the top valence subband is lhl for wider wel

关 键 词：量子阱 能带结构 张应变 

分 类 号：TN248[电子电信—物理电子学]