调制掺杂压缩应变多量子阱激光器的增益特性和线宽增强因子的理论研究

The Theoretical Analysis of Gain and Linewidth Enhancement Factor of Modulation-Doped Compress Strained Multi-Quantum-Well Lasers

本文首先从理论上分析并计算了压缩应变多量子阱激光器的增益特性，并且讨论了在多量子阱垒区进行ｐ型强调制掺杂的情况下，价带空穴的准费米能级的移动以及微分增益谱的变化。然后，计算了线宽增强因子（α）与应变大小和掺杂浓度以及注入载流子浓度之间的关系，结果发现压缩应变和增大载流子注入虽然能够减小α因子，但很难使它的零点波长对应于增益区，而利用调制掺杂技术能有效地使α因子的零点对应于增益区。在增大压缩应变和载流子注入浓度的情况下可以明显减小为使α因子变为零所需要的调制掺杂浓度。

The gain of compress strained multiple-quantum-well(CSMQW) lasers is theoretically analyzed and calculated.The energy movement of the hole Fermi level and the variation of the differential gain in the condition of p-type modulation doping(p-MD) in CSMQW barrier is also discussed.The relationship between the linewidth enhancement factor(α) and compress strain,p -MD density and injection carrier density is evaluated.The results show that strain effect and large injection can reduce α-parameter,however,it's difficult to make the zero-point of α- parameter penetrate to the gain region,while the use of the P-MD can effectively reduce α-parameter at some wavelength in the gain region to zero.The increase of compressed strain and injection carrier density can effectively improve the reduction of α-parameter caused by P-MD.