title: Photogenerated exciton dissociation in highly coupled lead salt nanocrystal assemblies.
abstract: Internanocrystal coupling induced excitons dissociation in lead salt nanocrystal assemblies is investigated. By combining transient photoluminescence spectroscopy, grazing incidence small-angle X-ray scattering, and time-resolved electric force microscopy, we show that excitons can dissociate, without the aid of an external bias or chemical potential gradient, via tunneling through a potential barrier when the coupling energy is comparable to the exciton binding energy. Our results have important implications for the design of nanocrystal-based optoelectronic devices.
authors.affiliation: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA. jwc47@cornell.edu
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Choi
authors.forename: Justin
authors.initials: J
authors.lastname: Luria
authors.forename: Byung-Ryool
authors.initials: BR
authors.lastname: Hyun
authors.forename: Adam C
authors.initials: AC
authors.lastname: Bartnik
authors.forename: Liangfeng
authors.initials: L
authors.lastname: Sun
authors.forename: Yee-Fun
authors.initials: YF
authors.lastname: Lim
authors.forename: John A
authors.initials: JA
authors.lastname: Marohn
authors.forename: Frank W
authors.initials: FW
authors.lastname: Wise
authors.forename: Tobias
authors.initials: T
authors.lastname: Hanrath
mesh_terms: D007854:Lead / Q000737:chemistry* / Q000528:radiation effects; D008027:Light; D046911:Macromolecular Substances / Q000737:chemistry / Q000528:radiation effects; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects; D010316:Particle Size; D012492:Salts / Q000737:chemistry / Q000528:radiation effects; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D012492:Salts; D007854:Lead