Inverse-Designed Dual-Resonant Plasmonic Nanotweezers for Enhanced Single Nanoparticle Photoluminescence

Abstract

The use of individual fluorescent nanoparticles for imaging molecular-scale biophysics is often hindered by a size-brightness trade-off, where reduced particle volumes lead to diminished signal-to-noise ratios and increased requirements for excitation power. Plasmonic nanotweezers have shown promise in their ability to position and enhance the emission from single nanoparticles. However, traditional designs are typically optimized for a single resonance, failing to simultaneously address optical trapping and emission enhancement. Here, we utilize a multiobjective topology optimization framework to design a dual-resonant plasmonic nanocavity. Our inverse-designed architecture provides simulta..