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Photogenerated exciton dissociation in highly coupled lead salt nanocrystal assemblies
Joshua J Choi1, Justin Luria, Byung-Ryool Hyun
1School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA. jwc47@cornell.edu
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.
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