Dynamic optical tweezers for metallic particle manipulation via tunable plasmonic fields

Abstract

Optical trapping has revolutionized various scientific disciplines with its non-invasive, high-resolution manipulation capabilities. However, conventional optical tweezers face limitations in effectively manipulating metallic particles due to their high reflectivity and associated scattering forces. Plasmonic tweezers, harnessing surface plasmons in metallic nanostructures, offer a promising solution by confining light to deep subwavelength scales and enhancing optical forces. However, dynamically manipulating metallic particles with plasmonic tweezers without mechanical adjustments remains a significant challenge. In this paper, we propose a novel approach utilizing dynamic optical tweezers with tunable plasmonic fields for metallic particle manipulation. By dynamically tailoring plasmonic fields with holograms, metallic particles can be manipulated without mechanical adjustments. Finite-difference time-domain simulations and Maxwell stress tensor calculations demonstrate the effectiveness of this technique, which offers simplicity, precision, and motionlessness in metallic particle manipulation. This advancement holds promise for applications in surface-enhanced Raman scattering, biosensing, super-resolved detection, and nanoparticle assembly, opening new avenues in plasmonic tweezers technology.