title: Plasmon dynamics in colloidal Au₂Cd alloy-CdSe core/shell nanocrystals.
abstract: Metal-semiconductor nanocrystal heterostructures are model systems for understanding the interplay between the localized surface plasmon resonances in the metal domain and the relaxation of the excited carriers in the semiconductor domain. Here we report the synthesis of colloidal Au₂Cd (core)/CdSe (shell) nanocrystal heterostructures, which were characterized extensively with several structural and optical techniques, including time-resolved fluorescence and broad-band transient absorption spectroscopy (both below and above the CdSe band gap). The dynamics of the transient plasmon peak was dominated by the relaxation of hot carriers in the metal core, its spectral shape was independent of the pump wavelength, and the bleaching lifetime was about half a picosecond, comparable with the value found in the AuCd seeds used for the synthesis.
authors.affiliation: Department of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
authors.forename: Pablo
authors.initials: P
authors.lastname: Guardia
authors.forename: Kseniya
authors.initials: K
authors.lastname: Korobchevskaya
authors.forename: Alberto
authors.initials: A
authors.lastname: Casu
authors.forename: Alessandro
authors.initials: A
authors.lastname: Genovese
authors.forename: Liberato
authors.initials: L
authors.lastname: Manna
authors.forename: Alberto
authors.initials: A
authors.lastname: Comin