Conflicting mechanisms have been proposed to explain the sub-bandgap turn-on behaviour of heterojunction organic light-emitting diodes (OLEDs). Here, by probing and modifying the OLED heterojunction, the authors show that band-to-band recombination is the most likely radiative recombination process.
- Sebastian Engmann
- Adam J. Barito
- David J. Gundlach