Plasmonic-Solitonic coupling structure

Abstract

The applications of optics, in particular non-linear optics, have joined the electrical ones in many contexts, often equaling or exceeding them thanks to the characteristics ensured by the physical nature of light such as high speed of propagation and low losses. In recent years, nanotechnologies combined with plasmon propagation are shaping a new development scenario that touches areas such as medicine, robotics or neurobiology. In fact, nano-devices are able to reproduce a very large number of functions ensuring very small dimensions. Among these, the applications of surface plasmon polariton waves are becoming more and more important, thanks to their peculiar behavior both as an electric wave and as a light wave. In this work we present an innovative structure consisting of a nano metallic waveguide on which it is possible to propagate a surface-plasmon- polariton signal at the interface with a photorefractive dielectric material. At the end of the guide, the diffracting light can generate, under suitable conditions, a self-confined light beam (bright-screening-photorefractive soliton). In this way the polariton plasmon waves propagating at the interface are automatically coupled within a soliton-based optical waveguide. By definition, soliton guides have very low propagation losses, opening the possibility of using this type of hybrid interconnection in extended complex circuits, for example as memories, thanks to the intrinsic plasticity of the photorefractive nonlinear refractive index