Enhancement of second-harmonic generation by coupling to long-range surface plasmons

Abstract

We show theoretically that by use of a new coupling geometry the second-harmonic light generated at the surface of a thin metal film can be enhanced dramatically through a coupling of the fundamental field to a long-range surface-plasmon mode. The resulting reflected harmonic intensity is predicted to be more than 2 orders of magnitude larger than that obtainable in the standard Kretschmann or Otto geometry.