title: Origin of efficiency roll-off in colloidal quantum-dot light-emitting diodes.
abstract: We study the origin of efficiency roll-off (also called "efficiency droop") in colloidal quantum-dot light-emitting diodes through the comparison of quantum-dot (QD) electroluminescence and photoluminescence. We find that an electric-field-induced decrease in QD luminescence efficiency-and not charge leakage or QD charging (Auger recombination)-is responsible for the roll-off behavior, and use the quantum confined Stark effect to accurately predict the external quantum efficiency roll-off of QD light-emitting diodes.
authors.affiliation: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shirasaki
authors.forename: Geoffrey J
authors.initials: GJ
authors.lastname: Supran
authors.forename: William A
authors.initials: WA
authors.lastname: Tisdale
authors.forename: Vladimir
authors.initials: V
authors.lastname: Bulović