论文标题
耦合胶体量子点分子的半导体bowtie nanoantenna
Semiconductor Bowtie Nanoantenna from Coupled Colloidal Quantum Dot Molecules
论文作者
论文摘要
自上而下的金属和介电材料的纳米植物体系结构表现出强大的拉曼和荧光增强功能，并与单分子传感相关，同时诱导了成色团发射的方向性，对单个光子源的影响。本文中，我们通过形成一个二聚体的两个四面体胶体量子点（CQD）的选择性尖端融合来合成最小的Bowtie Nanoantenna。尽管四面体单体发出非偏振光，但Bowtie结构表现出沿Bowtie轴的增强发射极化的纳米反胶功能，如理论上所预测的，并由单个粒子光谱揭示。理论还预测了Bowtie Epicenter上电场热点的形成。这用于选择性光诱导该位置的光催化金属生长，这与在黑暗条件下的自由尖端上的生长不同，从而证明了Bowtie二聚体功能作为光化学反应中心。我们的发现为适用于光学，传感和光催化的额外自下而上的Bowtie体系结构铺平了道路。
Top-down fabricated nanoantenna architectures of both metallic and dielectric materials demonstrated powerful functionalities for Raman and fluorescence enhancement with relevance to single molecule sensing, while inducing directionality of chromophore emission with implications for single photon sources. Herein, we synthesize the smallest bowtie nanoantenna by selective tip-to-tip fusion of two tetrahedral colloidal quantum dots (CQDs) forming a dimer. While the tetrahedral monomers emit non-polarized light, the bowtie architecture manifests nanoantenna functionality of enhanced emission polarization along the bowtie axis as predicted theoretically and revealed by single particle spectroscopy. Theory also predicts the formation of an electric-field hotspot at the bowtie epicenter. This is utilized for selective light induced photocatalytic metal growth at that location, unlike growth on the free tips in dark conditions thus demonstrating the bowtie dimer functionality as a photochemical reaction center. Our findings pave a path for additional bottom-up bowtie architectures applicable in optics, sensing and photocatalysis.
