title: Size- and temperature-dependent quantum confined dielectric effect in colloidal pbse and CdSe nanocrystals.
abstract: A new method is proposed to calculate the Stark shift induced by surface dielectric effect in colloidal nanocrystals. The effective mass approximation model is revised according to quantum confined dielectric effect. LUMO (the lowest unoccupied molecular orbital), HOMO (the highest occupied molecular orbital), band gap and Stark shift are calculated in CdSe and PbSe nanocrystals that bear significantly different physical properties. The calculated results fit well with the experimental data. The calculation of dielectric effect-induced Stark shift indicates that the quantum confined dielectric effect in PbSe and CdSe nanocrystals is size- and temperature-dependent, which is more notable in PbSe nanocrystals with a narrower band gap and results in the gentle variation of quantum confinement energy with particle size.
authors.affiliation: State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wenchao
authors.initials: W
authors.lastname: Cheng
authors.forename: Tieqiang
authors.initials: T
authors.lastname: Zhang
authors.forename: Tian
authors.initials: T
authors.lastname: Cui
authors.forename: Yiding
authors.initials: Y
authors.lastname: Wang
authors.forename: William W
authors.initials: WW
authors.lastname: Yu