2021/09/09 by Sunny Tiwari, Utkarsh Khandelwal, Tiwari, Sunny +5
Engineering · Materials Science · Physics and Astronomy · #Applied Physics (physics.app-ph) #FOS: Physical sciences #Gold and Silver Nanoparticles Synthesis and Applications #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics (physics.optics) #Orbital Angular Momentum in Optics #Plasmonic and Surface Plasmon Research #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2109.04281
openalex publication_date 2021/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Surface enhanced Raman scattering (SERS) is optically sensitive and\nchemically specific to detect single molecule spectroscopic signatures.\nFacilitating this capability in optically-trapped nanoparticles at low laser\npower remains a significant challenge. In this letter, we show single molecule\nSERS signatures in reversible assemblies of trapped plasmonic nanoparticles\nusing a single laser excitation (633 nm). Importantly, this trap is facilitated\nby the thermoplasmonic field of a single gold nanoparticle dropcasted on a\nglass surface. We employ bi-analyte SERS technique to ascertain the single\nmolecule statistical signatures, and identify the critical parameters of the\nthermoplasmonic tweezer that provide this sensitivity. Furthermore, we show the\nutility of this low power (\≈0.1 mW/\μm2) tweezer platform to trap\nsingle gold nanoparticle and transport assembly of nanoparticles. Given that\nour configuration is based on a dropcasted gold nanoparticle, we envisage its\nutility to create reconfigurable plasmonic metafluids in physiological and\ncatalytic environments, and can be potentially adapted as an in-vivo plasmonic\ntweezer.\n