Multimode surface plasmon excitation on metallic diffraction gratings

In this study, we report on multimode surface plasmon excitation on metallic diffraction gratings where the grating pitch is much larger than standard grating coupling surface plasmon excitation technique. With the gratings, multimode surface plasmons can be excited at the same time in the wavelength region using a white light source irradiation on the gratings. The grating coupling surface plasmon excitation was also studied by comparing with the theoretical surface plasmon dispersion curves.