Does the QD-LED have the roll-off effect when compared to OLED?

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Dauchpong Pimboonma

This picture comes from QD-LED fabrication. At the high level of brightness, their efficiency still decrease similarly to OLED. However, I am not sure the percent decreasing when compare between DQ-LED and OLED.

Kai Lin Woon

The roll-off effect could be the effect of self-heating, exciton-exciton quenching and some yet to be discovered. I am sure at high intensity, when there is so many excitons in the system, you will have exciton dissociation (coming from interaction of exciton with charged particles, exciton itself and the electric field). If the device is not that efficiency, the roll-off can be even more pronounced.

Hossein Zamani Siboni

QD-LED could also show severe efficiency roll-off. There are several factors that lead to the efficiency roll-off. In QD-LED Auger recombination (Charge exciton interaction) and electric field induced exciton quenching could be the main sources of roll-off. In OLEDs exciton-exciton interactions and charge exciton interactions are the known important causes of roll-off. I would say PHOLEDs at high current density could possibly show higher efficiency roll-off as exciton-exciton interactions quadratically increases with the driving current.