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DOE OSTI · 1803199

Using Fourier-Plane Imaging Microscopy for Determining Transition-Dipole-Moment Orientations in Organic Light-Emitting Devices

Kim, Jongchan·Zhao, Haonan·Hou, Shaocong·Khatoniar, Mandeep·Menon, Vinod·Forrest, Stephen R.
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Abstract

Here, we use Fourier-plane imaging microscopy (FIM) to determine the transition-dipole-moment orientation in doped organic emissive thin films. The use of FIM enables precise, sensitive, and rapid measurement of dipole orientation in the emission layer of an organic light-emitting device (OLED). An optical model of a stratified birefringent multilayer is introduced for interpreting results obtained by FIM. Using the model, we determine the average orientation of transition-dipole-moment vectors of three phosphorescent dopant emitters. The dipole alignment measured by FIM quantitatively explains the difference in OLED efficiencies using these archetype dopant molecules. FIM provides a nondestructive tool to measure and ultimately improve the outcoupling efficiency of OLEDs and other light-emitting devices.

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74 ATOMIC AND MOLECULAR PHYSICSPhysics

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Kim, Jongchan, Zhao, Haonan, Hou, Shaocong, Khatoniar, Mandeep, Menon, Vinod, Forrest, Stephen R.. 2020-09-17. Using Fourier-Plane Imaging Microscopy for Determining Transition-Dipole-Moment Orientations in Organic Light-Emitting Devices. https://doi.org/10.1103/physrevapplied.14.034048

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