Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Proc Natl Acad Sci U S A. 2013 Aug 20;110(34):13711-6. doi: 10.1073/pnas.1311866110. Epub 2013 Aug 5.
The nature of light interaction with matter can be dramatically altered in optical cavities, often inducing nonclassical behavior. In solid-state systems, excitons need to be spatially incorporated within nanostructured cavities to achieve such behavior. Although fascinating phenomena have been observed with inorganic nanostructures, the incorporation of organic molecules into the typically inorganic cavity is more challenging. Here, we present a unique optofluidic platform comprising organic molecules in solution suspended on a photonic crystal surface, which supports macroscopic Fano resonances and allows strong and tunable interactions with the molecules anywhere along the surface. We develop a theoretical framework of this system and present a rigorous comparison with experimental measurements, showing dramatic spectral and angular enhancement of emission. We then demonstrate that these enhancement mechanisms enable lasing of only a 100-nm thin layer of diluted solution of organic molecules with substantially reduced threshold intensity, which has important implications for organic light-emitting devices and molecular sensing.
光与物质的相互作用本质可以在光学腔中被显著改变，通常会诱导出非经典行为。在固态系统中，激子需要在纳米结构腔体内被空间集成，以实现这种行为。尽管已经观察到无机纳米结构中存在引人入胜的现象，但将有机分子纳入典型的无机腔中更具挑战性。在这里，我们提出了一种独特的光流体平台，其中包含在光子晶体表面上悬浮的溶液中的有机分子，其支持宏观的 Fano 共振，并允许与表面上任何位置的分子进行强且可调谐的相互作用。我们开发了该系统的理论框架，并与实验测量进行了严格比较，显示出发射的光谱和角度的显著增强。然后，我们证明这些增强机制可以实现仅为 100nm 厚的稀释有机分子溶液的激光发射，其阈值强度大大降低，这对有机发光器件和分子传感具有重要意义。
