Scalable Manufacturing of Low-Symmetry Plasmonic Nanospindle Arrays with Tunable Surface Lattice Resonance.

Geometry-dependent plasmonic surface lattice resonances (SLRs) have garnered great interest across a range of applications, including nanolasers, sensors, photocatalysis, and nonlinear optics. However, the rational fabrication of high-quality, low-symmetry, plasmonic nanoparticle arrays over large areas remains challenging. Herein, we report a versatile strategy for the scalable fabrication of centimeter-scale plasmonic nanospindle (NS) arrays with high positional and orientational precision. Our approach combines solvent-assisted soft lithography with in situ reduction of metal precursors, enabling the cost-effective production of large-area and well-ordered NS arrays without the need of specialized equipment. The Au NS arrays exhibit superior SLRs with a ultranarrow line width of 3.9 nm and a quality factor (Q-factor) of 309. The aspect ratio and lattice geometry of the NSs can be precisely tuned by applying mechanical strain to the stretchable elastomeric template, thus, allowing us to customize the SLR performance across the near-infrared spectrum. This technique enables the precise engineering of anisotropic nanoparticle arrays in a standard chemistry laboratory, opening new possibilities for advanced plasmonic devices.