First principle study of core/shell structure quantum dots

Authors :: Jingbo Li
Lin-Wang Wang
Source :: Li, Jingbo; & Wang, Lin-Wang. (2004). First principle study of core/shell structure quantum dots. Applied Physics Letter, 84(18). Lawrence Berkeley National Laboratory: Lawrence Berkeley National Laboratory. Retrieved from: http://www.escholarship.org/uc/item/65x1m3z5
Publication Year :: 2004
Publisher :: AIP Publishing, 2004.
Abstract: The electronic states of core/shell CdSe/CdS and CdSe/CdTe heterostructure quantum dots are studied by large-scale first-principles calculations. According to their natural band-offset alignments CdSe/CdS is a type-I heterostructure and CdSe/CdTe is a type-II heterostructure. We found that, the electron state changes very little, but the hole wave function in CdSe/CdS quantum dots has been localized within the core, while the hole wave function in CdSe/CdTe quantum dots is localized within the shell. The hole state in CdSe/CdTe quantum dots has drastically different characteristics as in CdSe and CdSe/CdS quantum dots. The band alignment, strain effect, and quantum confinement are all important to determine the electronic structures of these systems.