Hydrodynamic study of surface plasmon enhanced non-local second-harmonic generation

Abstract.

 A theoretical calculation of optical second-harmonic generation from a free-electron-like metal surface is presented. The metal is assumed to be semi-infinite with a flat surface. An excitation by a plane monochromatic electromagnetic wave incident upon the surface is considered in two geometries: (i) free surface and (ii) prism coupler in Otto configuration. The analytical expression of the second-harmonic reflectivity in the full hydrodynamic approach is derived. The important point is that the formalism we use leads to an analytical expression of this reflectivity. This allows an easy physical insight into the second-harmonic process at metal surfaces. The result is compared with previous calculations. It is also demonstrated how easily this calculation can be extended to the prism coupler.