Curved long-range surface plasmon-polariton waveguides

The propagation of the long-range surface plasmon-polariton mode in waveguides comprised of a curved thin metal film of finite width embedded in a homogeneous background dielectric is described. The curve and its mode are modelled in cylindrical coordinates using a rigorous vectorial numerical method and an absorbing boundary condition is applied on the radiating side of the bend. From the results obtained, it is confirmed that long-range structures are not incompatible with bending and that reasonably small radii of curvature can be used.