GaN基量子阱激子结合能和激子光跃迁强度

采用变分法，计算了GaN基量子阱中激子结合能和激子光跃选强度。计算结果表明，GaN基量子阱中激子结合能为10－55meV，大于体材料中激子结合能，并随着阱宽减小而增加，在临界阱宽处达到最大。结间带阶同样对激子结合能有着较大的影响，更大带阶对应更大的结合能。同时量子限制效应增加了电子空穴波函数空间重叠，因此加强了激子光跃迁振子强度，导致GaN/AlN量子阱中激子光吸收明显强于体材料中激子光吸收。

Exciton Binding Energy and Exciton Oscillator Strength of GaN-based Quantum-well Structure

The fundamental physics determining such excitonic properties in GaN-based quantum-well structure, as exciton binding energy and exciton oscillator strength is investigated. With the decrease of well width, the exciton binding energy increases and the maximum value is obtained at the critical well width. The band offset also affects the exciton binding energy, higher exciton binding energy correspoding to higher band offset. Quantum confinement increases the spatial overlap between an electron and a hole as a result of potential well confinement, and it also enhances the oscillator strength.