Dynamic tailoring large-area surface plasmon polariton excitation

Abstract

We propose and demonstrate a method for dynamically changing the patterning of the surface plasmon polariton (SPP) excitation over a large area under spatially inhomogeneous polarized illumination. By illuminating a 1D gold grating with shallow rectangular grooves with a spatially structured polarization beam of near-infrared light (780 nm), we selectively excited SPPs on an extended area. The parameters used to fabricate the grating coupler, matched the wave vector of the incident light with that of the SPP to achieve an efficient coupling. The incident wave illuminating the grating is a spatially inhomogeneous polarized beam. We designed local polarization states to control the local excitation of the SPP in order to pattern large areas. For real-time local control of the polarization state of the extended incident beam, we used a setup with a spatial light modulator and quarter-wave plate.