GRINSCH-SQW激光器波导特性的数值分析

Numerial analyses of waveguiding properties for GRINSCH SQW lasers

采用折射率台阶近似法将梯度折射率分别限制异质结单量子阱(GRINSCH—SQW)激光器波导结构中的缓变折射率层离散成折射率近似为常数的亚层,从而推导出此波导的近似本征方程,并用数值计算求解出波导对于基模的等效折射率。在此基础上,通过计算波导中垂直于激光器结平面方向上的光强近场分布,计算出与激光器的阈值电流有密切关系的光学常数——激光器有源层的光限制因子P以及各种波导结构参数对P的影响,同时计算了激光器的远场图形。计算结果可用于GRINSCH-SQW激光器波导结构参数的优化设计。

Step approximation of refractive index has been adopted to discrete the grad'ed-index layer of GRINSOH-SQW iaser into many sublayers to obtain the eigenvalue equation of the waveguide. The effective refractive index of the fundamental mode has been calculated by using numerical method to solve the eigenvalue equation. By calculating the near-field optical intensity distribution in the direction perpendicular to the junction plane, we have calculated the optical confinement faotorr which is closely rlated to the threshold current density. Based on this, influence of the waveguide parameters on the optical confinement properties has been discussed.