In organic light-emitting diodes (OLEDs), the low out-coupling efficiency of 20–30% limits the external quantum efficiency (EQE). Corrugated structures for OLED light extraction can increase the out-coupling efficiency by extracting the thin-film-guided mode as well as the surface plasmon (SP) mode. To further enhance the out-coupling efficiency of a corrugated OLED, we increase the refractive index contrast by incorporating a low-index light out-coupling layer in the device and the resulting OLED has an external quantum efficiency of 67%. By fabricating these corrugated OLEDs with the emitting layer located at the first and second antinode positions, we confirm that the enhanced extraction comes from the enhanced extraction of thin-film-guided modes.

中文翻译：

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折射率对比对使用低折射率LiF夹层的波纹OLED的外耦合效率的影响

在有机发光二极管（OLED）中，20-30％的低输出耦合效率限制了外部量子效率（EQE）。用于OLED光提取的波纹结构可以通过提取薄膜引导模式以及表面等离激元（SP）模式来提高输出耦合效率。为了进一步提高波纹OLED的输出耦合效率，我们通过在设备中引入低折射率的光输出耦合层来提高折射率对比度，并且所得OLED的外部量子效率为67％。通过制造发光层位于第一和第二波腹位置的这些波纹状OLED，我们确认增强的提取来自薄膜引导模式的增强提取。