Abstract
We demonstrate enhancement of photon to surface plasmon (SP) coupling using subwavelength metallic gratings and a variable gap Fabry-Pérot (FP) resonator. Strengthened SPs and light modes are launched by laser excitation in-coupling. Enhancements of out-coupled light intensity up to 15× are measured when compared to systems with no resonator. Out-coupled intensities show a FP type resonance when the resonator gap is scanned. Finite-element time and frequency domain simulations support measured results.