Simulation of transmission characteristics of nanometric bend circuits with open-type surface-plasmon gap waveguides

The transmission characteristics of nanometric bend circuits consisting of open-type surface plasmon polariton gap waveguides (o-SPGWs) are investigated by three-dimensional numerical simulation. The polygonal bend was used as a polygonal approximation of a circular bend. The scattering problem for this model is described by a volume integral equation and solved by an iterative technique based on the generalized minimum residual (GMRES) method and fast Fourier transform (FFT). The radiation loss from the o-SPGW polygonal bend structure is shown to be small compared to the propagation loss, an o-SPGWs are demonstrated to be useful as nanometric optical wire interconnects in nanometric optical circuits.