Surface plasmon polaritons with extended lifetime

The propagation distance of surface plasmon polaritons (SPPs) on metal nanowires is severely limited by their short lifetime, primarily due to strong metallic losses. In this work, we show that the lifetime-and thus the propagation distance-of SPPs can be significantly extended through the use of Fano resonances. Our FDTD simulations demonstrate that the SPP intensity at a fixed propagation distance can be enhanced by approximately 30 times. Furthermore, this enhancement factor is multiplicative with improvements achieved through other methods. We emphasize that this result represents only a starting point, as no optimization was performed due to limited computational resources.