Anyika Theodore, Hong Ikjun, Ndukaife Justus C
Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States.
Vanderbilt Institute of Nanoscale Science and Engineering, Nashville, Tennessee 37235, United States.
Nano Lett. 2023 Dec 27;23(24):11416-11423. doi: 10.1021/acs.nanolett.3c02543. Epub 2023 Nov 21.
Double Nanohole Plasmonic Tweezers (DNH) have emerged as a powerful approach for confining light to sub-wavelength volume, enabling the trapping of nanoscale particles much smaller than the wavelength of light. However, to circumvent plasmonic heating effects, DNH tweezers are typically operated off-resonance, resulting in reduced optical forces and field enhancements. In this study, we introduce a novel DNH design with a reflector layer, enabling on-resonance illumination while minimizing plasmonic heating. This design efficiently dissipates heat and redistributes the electromagnetic hotspots, making them more accessible for trapping nanoscale particles and enhancing light-matter interactions. We also demonstrate low-power trapping and release of small extracellular vesicles. Our work opens new possibilities for trapping-assisted Surface Enhanced Raman Spectroscopy (SERS), plasmon-enhanced imaging, and single photon emission applications that demand strong light-matter interactions.
双纳米孔等离子体镊子（DNH）已成为一种将光限制在亚波长体积内的强大方法，能够捕获比光波长小得多的纳米级粒子。然而，为了规避等离子体加热效应，DNH镊子通常在非共振状态下操作，导致光学力和场增强降低。在本研究中，我们引入了一种带有反射层的新型DNH设计，能够在最小化等离子体加热的同时实现共振照明。这种设计有效地散热并重新分布电磁热点，使它们更便于捕获纳米级粒子并增强光与物质的相互作用。我们还展示了对小细胞外囊泡的低功率捕获和释放。我们的工作为需要强光与物质相互作用的捕获辅助表面增强拉曼光谱（SERS）、等离子体增强成像和单光子发射应用开辟了新的可能性。
