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A Color-Tunable Alternating Current Organic Light Emitting Capacitor
Jongchan Kim1,2, Vivian Wang1,2, Seung Chan Kim3
1Department of Electrical Engineering and Computer Sciences, UC Berkeley, Berkeley, California 94720, United States.
Abstract:
We demonstrate an alternating current (AC) driven light emitting capacitor in which the color of the emission spectra can be changed via an applied AC frequency. The device has a simple metal-oxide-semiconductor (MOS) capacitor structure with an organic emissive layer, enabling facile fabrication processing. The organic emissive layer comprises a thin, submonolayer low energy dye layer underneath a thick host matrix (∼30 nm) with higher energy emitting dyes. The emission of the lower energy dyes dominates at low frequency, while the higher energy emission of the host matrix dominates at high frequency. This simple color tunable device could be used for full-color displays and lighting in the future.
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