Analysis of second-harmonic generation at metal surfaces

Abstract

We discuss the second-harmonic generation of light at metal surfaces within the hydrodynamic theory of the electron gas; expressions for the phenomenological parameters $a$ and $b$ of Rudnick and Stern are presented, and the possibility of a resonance in $a$ at optical or near-uv frequencies is discussed. A recent plasmon-enhanced experiment of Simon et al. is analyzed, and the use of such experiments to determine $a$ and $b$ is considered; new experiments are proposed to aid in such a determination.