Publication Type:Journal Article
Source:Phys. Rev. Lett., APS, Volume 110, Issue 21, p.217403 (2013)
Keywords:2013, 2013 and earlier
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.