[18p-E310-1~14] 12.4 Organic light-emitting devices and organic transistors

[18p-E310-4] Analysis of TADF-OLED characteristics based on external magnetic field effect (I)

〇Masaki Tanaka¹, Ryo Nagata¹, Hajime Nakanotani¹, Chihaya Adachi¹ (1.OPERA, Kyushu Univ.)

Keywords:TADF, external magnetic field effect

Device characteristics of TADF-OLEDs were analyzed based on external magnetic field effects (MFEs) of the devices. Under constant current condition, the changes in EL intensity (MEL) of TADF-OLEDs showed positive sign under external magnetic field, which suggests that the exciton quenching processes are suppressed by applied magnetic field. The MEL responses can be separated into two different mechanisms, i.e., polaron-pair mechanism and triplet-polaron interaction (TPI) mechanism. Furthermore, the amplitudes of the MEL of the devices based on the emitters with long triplet exciton lifetimes were larger than these with short exciton lifetimes, which clearly suggests that the effect of triplet exciton quenching through TPI is large in the device with long exciton lifetime. This study helps comprehensive understandings of MFEs and dynamics of exciton in TADF-OLEDs.