Quantum confinement of Te bound exciton in ZnSe/ZnSe_(1-x)Te_x and ZnSe/Zn_(1-y)Cd_ySe quantum wells

摘要

The quantum confinements of an exciton bound to a single Te (X/Te) and to many Te (X/Te_n) were observed for the first time in ZnSe/Zn_(1-y)Cd_ySe quantum wells with a thin ZnSe_(1-x)Te_x (very low x < 0.01) layer inserted at the center of a Zn_(1-y)Cd_ySe quantum well. The binding energies of X/Te for the 5.0, 2.5, and 1.4 nm wells were 69, 81, and 83 meV, respectively. In the case of ZnSe/ZnSe_(1-x)Te_x quantum well structures, the quantum confinement of a deep energy level, Te cluster bound exciton, was investigated. Current results imply a tiny wave-function size for the X/Te, X/Te_n, and exciton bound to a Te cluster.