title: Continuous layer gap plasmon resonators.
abstract: We demonstrate both theoretically and experimentally that a gold nanostrip supported by a thin dielectric (silicon dioxide) film and a gold underlay forms an efficient (Fabry-Perot) resonator for gap surface plasmons. Periodic nanostrip arrays are shown to exhibit strong and narrow resonances with nearly complete absorption and quality factors of ~15-20 in the near-infrared. Two-photon luminescence microscopy measurements reveal intensity enhancement factors of ~120 in the 400-nm-period array of 85-nm-wide gold strips atop a 23-nm-thick silica film at the resonance wavelength of ~770 nm. Excellent resonant characteristics, the simplicity of tuning the resonance wavelength by adjusting the nanostrip width and/or the dielectric film thickness and the ease of fabrication with (only) one lithography step required make the considered plasmonic configuration very attractive for a wide variety of applications, ranging from surface sensing to photovoltaics.
authors: Institute of Technology and Innovation (ITI), University of Southern Denmark, Niels Bohrs Allé 1, DK-5230 Odense M, Denmark. mgni@iti.sdu.dk
authors: Michael G
authors: MG
authors: Nielsen
authors: Dmitri K
authors: DK
authors: Gramotnev
authors: Anders
authors: A
authors: Pors
authors: Ole
authors: O
authors: Albrektsen
authors: Sergey I
authors: SI
authors: Bozhevolnyi
mesh_terms: D006046:Gold / Q000737:chemistry; D036103:Nanotechnology; D012822:Silicon Dioxide / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D006046:Gold; D012822:Silicon Dioxide