Optical Binding of Metal Nanoparticles Self‐Reinforced by Plasmonic Surface Lattice Resonances

• Published in: Advanced optical materials Vol. 11; no. 24
• Main Authors: Qi, Tailei, Nan, Fan, Yan, Zijie
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-12-2023
• Subjects: Arrays; Binding; Nanoparticles; optical binding; optical matters; Plasmonics; self‐assembly; surface lattice resonance; Surface plasmon resonance
• ISSN: 2195-1071; 2195-1071
• DOI: 10.1002/adom.202301158

Optical binding of metal nanoparticles (NPs) provides a promising way to create tunable photonic materials and devices, where the ultrastrong interparticle interaction is generally attributed to the localized surface plasmon resonances of NPs. Here, it is revealed that the optical binding of metal NPs can be self‐reinforced by the plasmonic surface lattice resonances (PSLRs) associated with the discrete NP arrays. Through simulations and experiments, it is demonstrated that PSLRs can spontaneously arise in optically bound gold NP chains with just a few NPs when they are relatively large, e.g., 150 nm in diameter. Additionally, the PSLRs are enhanced by increasing the chain length, leading to stronger optical binding stiffness. These results reveal a previously unidentified factor that contributes to the ultrastrong optical binding of metal NPs. More importantly, this study presents a prospect for building freestanding and reconfigurable NP arrays that naturally support PLSRs for sensing and other applications.
Plasmonic surface lattice resonance can spontaneously arise in an optically bound Au nanoparticle chain consisting of just a few relatively large nanoparticles. This resonance enhances the scattering of laser light by the nanoparticles, leading to stronger optical binding interactions. This discovery holds promise for building freestanding and reconfigurable nanoparticle arrays that naturally support surface lattice resonance for various applications.