EAGER: Distributed Feedback/Distribute Gain Fabry-P?rot Microcavities for Organic Light Emitting Diodes

非技术：有机半导体是一种新型材料，具有低成本加工和灵活性等吸引人的特性。这导致了有机发光二极管(OLED)在手机和电视显示器中的广泛采用。然而，有一个重要的应用是不可能的：激光。该项目将通过研究周期性光学微结构中光与物质的相互作用，为电驱动有机激光器奠定基础。一系列反射镜将创建一种分布式光学结构，仅允许特定颜色的光以特定角度通过。这些反射镜还将用作OLED的电极，将光发射限制在反射镜结构中的特定位置。该团队将把建模与器件制造和表征结合起来，以确定光学微结构对光发射的影响。该项目将把材料和器件结构的组合推向激光门槛。该项目还将为研究和开发建立一个公开可用的材料光学和电学性质数据库。将举办有机光电子学夏季研讨会，为高中STEM学生提供实践经验，探索前沿研究领域。技术：电泵浦有机二极管激光器具有巨大的潜力，仍然是有机光电子学中尚未解决的主要挑战之一。微腔几何结构在光泵浦系统中显示出巨大的前景，但低的载流子迁移率和光学损耗阻碍了基于有机发光二极管(OLED)的器件接近激光阈值。该方案使用分布式反馈和分布式增益几何结构，将电传输与光路长度解耦。电导仅通过100 nm的OLED厚度发生，而功能光路长度可能高出许多个数量级，这取决于堆叠层的数量和反射镜的反射率。在镜面具有节点的驻波模式最大限度地减少了光学损耗。发射层上相应的安替诺节点最大限度地增加了受激发射的可能性。在制造器件角度分辨电致发光光谱的反馈的驱动下，将使用多种建模技术来优化微腔设计。该项目将首先探索腔厚度和腔内发射极位置对跨越多个半波长模式的单层器件的影响。反馈机制和增益介质随后将分布在多个堆叠设备上，目标是与给定发射器分子的电致发光峰值一致的共振半波长模式。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical:Organic semiconductors are a novel class of materials with attractive properties such as low-cost processing and flexibility. This has led to the widespread adoption of organic light-emitting diodes (OLEDs) into displays for mobile phones and TVs. One important application, however, has not been possible: lasers. This project will lay the foundations for electrically-driven organic lasers by investigating the interaction of light and matter in periodic optical microstructures. A series of mirrors will create a distributed optical structure that only allows certain colors of light to pass through at specific angles. These mirrors will also function as the electrodes for OLEDs, confining light emission to specific locations within the mirror structure. The team will combine modeling with device fabrication and characterization to determine the effect of the optical microstructure on light emission. The project will push the combination of materials and device structure toward the lasing threshold. The project will also produce a publicly-available database of optical and electronic properties of materials for research and development. A summer workshop on organic optoelectronics will be organized, providing hands-on experience for high school STEM students to explore a cutting-edge research field.Technical:Electrically-pumped organic diode lasers offer immense potential and remain one of the major unsolved challenges in organic optoelectronics. Microcavity geometries show significant promise in optically-pumped systems, yet low carrier mobility and optical losses prevent devices based on organic light-emitting diodes (OLEDs) from approaching the lasing threshold. This project uses a distributed feedback and distributed gain geometry, decoupling the electrical transport from the optical path length. The electrical conduction occurs through only 100 nm of the OLED thickness, while the functional optical path length may be many orders of magnitude higher, depending on the number of stacked layers and the reflectivity of the mirrors. Standing-wave modes with nodes at the mirror surfaces minimize optical losses. The corresponding antinodes at the emission layer maximize the possibility of stimulated emission. Multiple modeling techniques will be used to optimized the microcavity design, driven by feedback from angle-resolved electroluminescence spectra of fabricated devices. The project will first explore the effects of cavity thickness and emitter position within the cavity for single-layer devices spanning multiple half-wavelength modes. The feedback mechanism and gain medium will then be distributed over multiple stacked devices, targeting the half-wavelength mode with resonance coincident with the electroluminescense peak of a given emitter molecule.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.