Nanoimprinted Bragg Gratings for Long-Range Surface Plasmon Polaritons Fabricated via Spin Coating of a Transparent Silver Ink

We designed, fabricated, and characterized novel long-range surface plasmon polariton waveguides based on Bragg gratings (LRSPPW-BGs) via spin coating of a transparent silver ink on nanoimprinted polymeric patterns at low temperature in the absence of a vacuum system. For 20-nm-thick and 8-μm-wide LRSPPW-BGs of lengths in excess of 500 μm , the measured reflectances are greater than 90% at a Bragg wavelength of ~1532 nm. For a 20-nm-thick, 8- μm-wide, and 1000-μm-long LRSPPW-BG, the full width at half maximum of a reflectance is determined to be 1.89 nm. The use of spin-coatable silver ink combined with the nanoimprint technique may represent a viable new route for cost effective and simple fabrication of LRSPPW-BGs.