应变多量子阱激光器的结构稳定性

Structure stability of stranined MQW laser

通过计算应变多量子阱中的净应力和应变弛豫，讨论了激光器结构中应变多量子阱的稳定性。净应力是失配位错增殖的驱动力，是应变多量子阱稳定的重要判据。因此，用单结点模型计算了应变多量子阱结构中的净应力。计算结果表明，净应力的最大值在应变多量子阱结构中的位置与阱层和垒层的厚度以及阱层的失配有关，非应变垒层和盖层能在一定程度上稀释净应力。在此基础上，利用动力学模型计算了应变多量子阱的应变弛豫。

In this paper,the stability of strained MQWs in laser structure is discussed in terms of the calculation of net stress and strain relaxation.The net stress is a driving force of misfit dislocation multiplication and is a very important factor for strained MQWs stability.Thereby we calculate the net stress by using the single-kink model.Our results show that the position of maximum net stress is dependent on the thickness of barrier and well and the mismatches in the well.Both lattice-matched barrier and capping layer can dilute the net stress to a certain degree. We then calculate the strain relaxation using the dynamic model of dislocations.