Surface-Nanocorrugation-Controlled Selectivity and Tunability of Plasmon Resonances: Application to Resonance Energy Transfer

Precise control of plasmonic resonances in metal nanoparticles is essential for tuning optoelectronic processes. Resonance energy transfer (RET) between chromophores often constitutes a key step in many related applications. While plasmonic enhancement of RET has been widely reported, most studies have focused on pristine nanoparticles without deliberate surface morphology engineering. Here, we develop an inductor–capacitor circuit model combined with finite-difference time-domain simulations to study how surface corrugations modulate localized surface plasmon polaritons (LSPPs) and, in turn, the rate of RET between nearby chromophores. In corrugated silver nanorods, transverse electron oscillations emerge alongside conventional longitudinal modes, and their interplay drives expansion or contraction of the electron gas, producing distinct red- or blueshifts of LSPP resonances. The corrugation height determines the magnitude of these shifts, whereas periodicity governs mode selectivity, with maximum shifts occurring when the plasmonic field and surface morphology are in or out of phase. Model predictions agree with reported experimental results across diverse nanoparticle geometries, establishing surface nanocorrugation as a powerful tool for plasmonic spectral engineering with direct implications for RET-based nanoscale photonic applications.