Surface recombination and charged exciton in nanocrystal quantum dots on photonic crystals under two-photon excitation.

ABSTRACT: In this study, the two-photon excited fluorescence spectra from cadmium selenide quantum dots (QDs) on a silicon nitride photonic crystal (PhC) membrane under femtosecond laser irradiation were investigated. These spectra can be fit to a tri-Gaussian function in which one component is negative in amplitude, and in which the Gaussian components with positive amplitude are assigned to exciton emission and charged-exciton emission and that with negative amplitude is assigned to absorption from surface recombination. The photonic crystal enhance the charged-exciton emission and exciton emission and, at the same time, also the absorption from surface recombination. Both the charged-exciton emission and the surface recombination are related to Auger recombination; therefore, the photonic crystal

SUBMITTER: Xu X 

PROVIDER: S-EPMC4047539 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature