Wide Range Color Tuning in Single Emissive Layer Organic Light Emitting Transistors

Usinga single emissive layer, color tuning within a wide visiblelight range (from blue to red) is achieved in organic light emittingtransistors. In the fabricated devices, both the gate and drain electrodesare made of aluminum (acting as an optical resonator), and the emissivelayer thickness is adjusted to vary the distance between them. Remarkably,layer thickness variation, which is responsible for color tuning,does not affect the optical turn-on voltages, in contrast to organiclight emitting diode devices. Significantly enhanced external quantumefficiencies are also observed for thick emissive layer devices. Opticalsimulations that accurately match experimental results indicate thatthe wide range of color tunability is mainly due to an outcouplingeffect through the Fabry-Perot cavity. Our study presents asimpler and more flexible alternative for display technology design.

Automated summary

Using a single emissive layer, this study achieved color tuning within a wide visible light range (from blue to red) in organic light emitting transistors. The color tuning does not affect the optical turn-on voltages and significantly enhanced external quantum efficiencies are observed for devices with a thick emissive layer. The wide range of color tunability is mainly due to an outcoupling effect through the Fabry-Perot cavity.