Plasmonic response of bent silver nanowires for nanophotonic subwavelength waveguiding.

We have imaged, with electron energy loss spectroscopy, the plasmonic response of straight and bent silver nanowires for their potential use in nanophotonic circuits. The guided surface plasmon polaritons appear unaffected by the presence of sharp kinks and corners in the nanowires studied, shown by direct imaging of excited Fabry-Perot-type resonances. Nanoscale detection is extended down to 0.17 eV, enabling detailed measurements of the spatial extent and dispersion of guided surface plasmon polaritons at low wave numbers. The experimental measurements are in excellent agreement with calculations, and the results are relevant in the design of integrated nanophotonic circuits and devices.