通过转移矩阵法和有效折射率法计算了9.0μm GaAs基量子级联激光器波导的模式损耗和限制因子,从而对其波导结构进行优化.计算中考虑了各外延层的厚度、脊宽和腔长的影响.给出了在较低阈值下节约材料生长时间的各外延层厚度.
Improved waveguide designs for 9.0μm GaAs-based quantum cascade laser (QCL) structures are presented. Modal losses and confinement factors are calculated for TM modes with the transfer matrix method (TMM) and effective index method (EIM). The thicknesses of the cladding layer and waveguide layer, the ridge-width, and the cavity length are all taken into account. Appropriate thicknesses of epilayers are given with lower threshold gain and more economical material growth time.