title: Quantum-confined emission and fluorescence blinking of individual exciton complexes in CdSe nanowires.
abstract: One-dimensional semiconductor nanostructures combine electron mobility in length direction with the possibility of tailoring the physical properties by confinement effects in radial direction. Here we show that thin CdSe quantum nanowires exhibit low-temperature fluorescence spectra with a specific universal structure of several sharp lines. The structure strongly resembles the pattern of bulk spectra but show a diameter-dependent shift due to confinement effects. Also the fluorescence shows a pronounced complex blinking behavior with very different blinking dynamics of different emission lines in one and the same spectrum. Time- and space-resolved optical spectroscopy are combined with high-resolution transmission electron microscopy of the very same quantum nanowires to establish a detailed structure-property relationship. Extensive numerical simulations strongly suggest that excitonic complexes involving donor and acceptor sites are the origin of the feature-rich spectra.
authors.affiliation: Institute of Physical Chemistry, University of Hamburg , Grindelallee 117, 20146 Hamburg, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Franz
authors.forename: Aina
authors.initials: A
authors.lastname: Reich
authors.forename: Christian
authors.initials: C
authors.lastname: Strelow
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Andreas
authors.initials: A
authors.lastname: Kornowski
authors.forename: Tobias
authors.initials: T
authors.lastname: Kipp
authors.forename: Alf
authors.initials: A
authors.lastname: Mews
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D011789:Quantum Theory; D018036:Selenium Compounds / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D018036:Selenium Compounds; C058667:cadmium selenide
keywords: CdSe; Quantum nanowires; blinking; donor−acceptor pairs; exciton complexes