Pulsed electroluminescence from organic bilayer light emitting diodes

Transient electroluminescence (EL) from organic bilayer light emitting diodes featuring an interfacial blockade for holes and electrons was studied. At the end of the driving voltage pulse an EL spike is observed whose magnitude exceeds the cw‐EL intensity by up to two orders of magnitude. The effect is attributed to an increase of the recombination probability of minority carriers (electrons) with majority carriers upon switching off the external field.