title: Electronic states and luminescence in higher fullerene/porous Si nanocrystal composites.
abstract: Photoluminescence (PL) measurements have been performed on the nanocomposites of higher fullerene-coupled porous silicon (PS) nanocrystals. For the C70PS and C76(78)PS nanocomposites, the PL spectra show a pinning wavelength at approximately 565 nm and for the C84PS and C94PS nanosystems the pinning wavelength is at approximately 590 nm. The PL pinning property is closely related to the sorts of the coupled fullerenes. A band mixing model of direct and indirect gaps in a nanometer environment consisting of nc-Si core, SiO2 surface layer, and coupled fullerene has been proposed for calculation of electronic states. Good agreement is achieved between the experiments and theory.
authors.affiliation: National Laboratory of Solid State Microstructures, Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China. hkxlwu@nju.edu.cn
authors.forename: X L
authors.initials: XL
authors.lastname: Wu
authors.forename: Z H
authors.initials: ZH
authors.lastname: Deng
authors.forename: F S
authors.initials: FS
authors.lastname: Xue
authors.forename: G G
authors.initials: GG
authors.lastname: Siu
authors.forename: Paul K
authors.initials: PK
authors.lastname: Chu