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arXiv · 1608.05242

Manipulation of the electroluminescence of organic light-emitting diodes via fringe fields from patterned magnetic domains

Nicholas J. Harmon·Michael E. Flatté
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Abstract

We predict very large changes in the room-temperature electroluminescence of thermally-activated delayed fluorescence organic light emitting diodes near patterned ferromagnetic films. These effects exceed the changes in a uniform magnetic field by as much as a factor of two. We describe optimal ferromagnetic film patterns for enhancing the electroluminescence. A full theory of the spin-mixing processes in exciplex recombination, and how they are affected by hyperfine fields, spin-orbit effects, and ferromagnetic fringe field effects is introduced, and is used to describe the effect of magnetic domain structures on the luminescence in various regimes. This provides a method of enhancing light emission rates from exciplexes and also a means of efficiently coupling information encoded in magnetic domains to organic light emitting diode emission.

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Nicholas J. Harmon, Michael E. Flatté. 2016-08-18. Manipulation of the electroluminescence of organic light-emitting diodes via fringe fields from patterned magnetic domains. https://doi.org/10.1063/1.4971332

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