论文标题
通过有机分子和量子点之间的强耦合来实现有效的光子上转换
Efficient Photon Upconversion Enabled by Strong Coupling Between Organic Molecules and Quantum Dots
论文作者
论文摘要
有机分子和无机量子点之间形成的杂种结构可以利用其不同的特性来实现独特的光物理转化。这些材料之间的电子耦合通常很弱，导致光激发荷载载流子在其表面上定位在点或分子上。但是，我们表明，通过将共价结合蒽分子与硅量子点结合的化学连接器从碳碳单键与双键结合到硅量子点，我们进入了一个强耦合方案，激发载体在空间上在蒽和硅和硅子上都在空间上下降。通过将系统推向离域化，我们设计了效率更高（17.2％）和较低阈值强度（0.5 w/cm^2）的光子上转换系统，而不是相应的弱耦合系统。我们的结果表明，通过靶向链接化学实现的分子和纳米结构之间的强耦合为在光驱动应用中量身定制特性提供了新的途径。
Hybrid structures formed between organic molecules and inorganic quantum dots can accomplish unique photophysical transformations by taking advantage of their disparate properties. The electronic coupling between these materials is typically weak, leading photoexcited charge carriers to spatially localize to a dot or a molecule at its surface. However, we show that by converting a chemical linker that covalently binds anthracene molecules to silicon quantum dots from a carbon-carbon single bond to a double bond, we access a strong-coupling regime where excited carriers spatially delocalize across both anthracene and silicon. By pushing the system to delocalize, we design a photon upconversion system with a higher efficiency (17.2%) and lower threshold intensity (0.5 W/cm^2) than that of a corresponding weakly-coupled system. Our results show that strong coupling between molecules and nanostructures achieved through targeted linking chemistry provides a new route for tailoring properties in materials for light-driven applications.
