Magnetically Responsive Tuning of Plasmonic Nanostructures

金属纳米颗粒可以比人类头发的直径小10,000倍，并且可以由金和银等金属制成。它们与光的相互作用使它们适用于从传感器到视觉显示器的应用。 虽然许多类型的颗粒是球形的，但它们也可以制成更复杂的形状。在化学系大分子、超分子和纳米化学项目的支持下，加州大学河滨分校的Yadong Yin教授正在开发将磁性成分纳入棒状金属纳米结构的方法。 混合结构的光学性质可以通过施加磁场来控制，从而产生新的功能。该项目的发现正在提高我们创造新金属纳米颗粒的能力，并可能对化学检测，生物医学传感和信息加密等应用产生广泛影响。 这项工作还为跨学科领域的研究生提供培训机会。此外，与当地学校和社区学院的外联活动正在吸引学生，特别是来自代表性不足群体的学生参加研究性学习。该研究小组旨在开发制造等离子体/磁性混合纳米结构的有效方法，以实现等离子体特性的主动调谐，并探索其在光致动和信息加密中的独特应用。提出了三种非常规的方法，包括两个模板过程和一个逐步的“嵌入和生长”的过程，以实现不仅混合组合物，而且自发取向协会的磁性和等离子体成分。等离子体激元和磁性部件之间的保证对准使得可以以高度均匀和可控的方式精确地调谐等离子体激元激发模式。所得的杂化纳米材料具有高的结构完整性和胶体稳定性，并且可以在溶剂或聚合物基质中加工以用于制造功能器件。该提案还旨在利用混合纳米棒的角度依赖等离子体特性和磁取向对准的优势，以展示其在两个独特而重要的应用中的用途，包括光致动器和信息加密（防伪）该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查进行评估，被认为值得支持的搜索.

Metal nanoparticles can be 10,000 times smaller than the diameter of a human hair, and can be made from metals such as gold and silver. Their interactions with light make them useful for applications ranging from sensors to visual displays. While many types of particles are spherical, they can also be made into more complicated shapes. With support from the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Yadong Yin of the University of California-Riverside is developing ways to incorporate magnetic components into rod-shaped metal nanostructures. The optical properties of the hybrid structures can be controlled by applying magnetic fields, giving rise to new functionality. The discoveries from the project are advancing our ability to create new metal nanoparticles, and could have broad implications for applications such as chemical detection, biomedical sensing, and information encryption. The work is also providing training opportunities for graduate students in interdisciplinary fields. In addition, outreach to local schools and community colleges is engaging students, especially those from underrepresented groups, in research-based learning. The research team aims to develop effective approaches for fabricating plasmonic/magnetic hybrid nanostructures to achieve active tuning of plasmonic properties and explore their unique applications in photoactuation and information encryption. Three unconventional approaches are proposed, including two templating processes and one stepwise "embed and grow" process, to achieve not only the hybrid composition but also the spontaneous orientational association of the magnetic and plasmonic components. The guaranteed alignment between the plasmonic and magnetic components makes it possible to precisely tune the plasmonic excitation modes in a highly uniform and controllable manner. The resulting hybrid nanomaterials have high structural integrity and colloidal stability and can be processed in solvents or polymer matrices for fabricating functional devices. The proposal also aims to take the advantages of the angular dependent plasmonic property and the magnetic orientational alignment of the hybrid nanorods to demonstrate their uses in two unique and important applications including photoactuators and information encryption (anti-counterfeiting) devices.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.