Aug. 10, 2020
- A team of researchers in the group of Professor Russell Holmes has reported in the journal Science Advances a previously unknown source of luminescence loss in organic light-emitting devices (OLEDs). OLEDs are a ubiquitous display technology that find application in mobile phones, televisions, and wearable electronics. The team consisted of graduate students John Bangsund and Nolan Concannon, as well as undergraduate Jack Van Sambeek. Carefully investigating the behavior of OLEDs at low applied voltage bias, the team identified the presence of significant exciton quenching losses coming from interactions with accumulated charge carriers induced by a spontaneous polarization field. Previous work had argued that carrier-based quenching losses should only appear under high injection, and that losses at low-bias originate more from charge carrier leakage and recombination. This finding is important in that it forces a revision of the factors that impact luminescence efficiency in OLEDs and hence, revised device design rules.
This work was supported by DuPont Electronics and Imaging, the National Science Foundation, and Ronald L. and Janet A. Christenson.
Related Link: https://doi.org/10.1126/sciadv.abb2659