极性半导体窄量子阱中的激子结合能(英文)

Binding Energies of Excitons in Narrow Quantum Wells of Polar Semiconductors

计及电子－声子相互作用计算了极性－极性半导体量子阱中激子的结合能．考虑空穴带质量的各向异性，利用变分法计算了在量子阱中与电子和空穴相耦合的两支体纵光学声子模和四支界面光学声子模对激子结合能的贡献．给出并讨论了一些系统的数值结果．结果表明体声子和界面声子对激子的结合能起着重要的作用，结合能的声子效应对电子和空穴的质量比是敏感的．

The binding energy of an exciton in a quantum well of polar polar semiconductors is calculated including electron phonon interaction. There are four branches of interface optical (IO) modes besides the bulk longitudinal optical (LO) modes confined in the well coupling with both the electron and hole. The anisotropic band mass of the hole is considered. The phonon contributions to the binding energy are obtained by a variational calculation. The numerical results for some systems are given and discussed. It is shown that both the bulk and interface optical phonons play important roles for the binding energies of the excitons. The phonon effect on the binding energy is sensitive to the electron hole mass ratio. The validity of our calculation is also discussed.