InAs/GaAs量子点激光器的增益和线宽展宽因子  

Gain and Linewidth Enhancement Factor of InAs/GaAs Quantum-dot Laser Diodes

作　　者：许海鑫[1] 王海龙[1] 严进一[2] 汪洋[2] 曹春芳[2] 龚谦[2] 

机构地区：[1]山东省激光偏光与信息技术重点实验室曲阜师范大学物理系,山东曲阜273165 [2]中国科学院上海微系统与信息技术研究所信息功能材料国家重点实验室,上海200050

出　　处：《发光学报》2015年第5期567-571,共5页Chinese Journal of Luminescence

基　　金：山东省自然科学基金(ZR2014FM011);信息功能材料国家重点实验室开放课题(SKL201307)资助项目

摘　　要：利用气源分子束外延技术生长In As/Ga As量子点激光器材料,制作了由5层量子点组成的500μm腔长的激光器。首次使用增益拟合和波长加权的方法计算了激光器的线宽展宽因子。其中,增益拟合是对Hakki-Paoli方法计算增益的重要补充,对判断不同电流下的增益是否饱和具有重要作用。对最大模式增益求导数,当电流为50 m A时,差分增益最大值为1.33 cm-1/m A,然后迅速减小到0.34 cm-1/m A,此时电流为57m A（≈0.99Ith）。第一次使用加权波长来计算中心波长的移动,发现Δλ慢慢减小直至接近于0。整个计算方法避免了在直接选取数据点时造成的误差,线宽展宽因子计算值为0.12~2.75。A 500-μm-long cavity laser diode with 5 layers of In As quantum dot was fabricated. The laser materials were grown by gas-source molecular beam epitaxy. For the first time,the linewidth enhancement factor was acquired by gain fitting and weighted wavelength. Gain fitting is an important complement to Hakki-Paoli method,and plays an important role in evaluating whether the gain is saturation. The differential modal gain was evaluated by numerical differentiation of the maximum modal gain. The differential modal gain showed a maximum of 1. 33 cm- 1/ m A at 50 m A,and dropped off to 0. 34 cm- 1/ m A at 57 m A（ ≈0. 99Ith）. The weighted average wavelength was treated as central wavelength in order to calculate the wavelength movement. It was found that Δλ decreased slowly until closed to zero. The new method avoids the error due to selecting the data points,and the value of linewidth enhancement factor is from 0. 12 to 2. 75.

关 键 词：激光器增益 差分增益 波长移动 线宽展宽因子 

分 类 号：TN248.4[电子电信—物理电子学]