外电场对InGaAsP/InP量子阱内激子结合能的影响

在有效质量近似下采用变分法计算了InGaAsP/InP量子阱内不同In组分下的激子结合能，分析了结合能随阱宽和In组分的变化情况，并且讨论了外加电场对激子结合能的影响. 结果表明：激子结合能是阱宽的一个非单调函数，随阱宽的变化呈现先增加后减小的趋势；随着In组分增大，激子结合能达到最大值的阱宽相应变小，这与材料的带隙改变有关；在一定范围内电场的存在对激子结合能的影响很小，但电场强度较大时会破坏激子效应. 关键词： 激子 InGaAsP/InP量子阱 结合能 电场

External electric field effect on exciton binding energy in InGaAsP/InP quantum wells

Exciton binding energies in InGaAsP/InP quantum well with different contents of In are calculated through variational method in the effective mass approximation. The variation of exciton binding energy as a function of well width, In content, and applied external electric field is studied. It is shown that the exciton binding energy is a non-monotonic function of well width. It increases first until reaching a maximum, and then decreases as the well width increases farther. In addition, with the increase of In content, the well width should increase to reach the maximum value of exciton binding energy. It is also found that the external electric field has little effect on binding energy, but when the electric field is large enough, it will destroy the excitonic effect. These results may provide some theoretical basis for the design and control of InGaAsP/InP optical devices.
Keywords： exciton InGaAsP/InP quantum well binding energy electric field