Observation of Fano line shapes arising from coupling between surface plasmon polariton and waveguide modes

We demonstrate experimentally the generation of narrow Fano line shapes in planar multilayer structures. The Fano line shape originates from coupling between a high loss surface plasmon polariton mode with a low loss planar waveguide mode. The line shape is shown to depend strongly on the structural parameters that govern the position of the waveguide mode and the coupling strength, and to be in good agreement with results of electromagnetic calculations. (C) 2016 AIP Publishing LLC.