Optical second-harmonic generation for studying surfaces and interfaces

Abstract

Optical second-harmonic generation (SHG) is one of a number of new optical techniques offering monolayer sensitivity. It is shown how the non-linear optical response of a medium can produce a surface-specific second-harmonic signal. The type of information available from SHG studies is outlined. A brief historical review is followed by discussion of recent UHV studies of surface and interface SHG from single-crystal metal and semiconductor systems.