Figure 4
The physical model for efficient spin-conversion and energy up-converted electroluminescence at organic heterojunctions.
Electrons are injected into C60 at a spin ratio of 1:3. As the T1 of C60 is higher in energy than T1 of rubrene a Dexter type triplet energy transfer (TET) from C60 to rubrene is favourable. The TET process then populates triplets in rubrene that undergo triplet-triplet annihilation (TTA) to generate a singlet. The generation of singlet through this route then decays to ground state through UC-EL in rubrene.
