Second harmonic generation at thin film silver electrodes via surface polaritons

摘要

The generation of second harmonic light from a silverndash;mica capacitor and from thin film silver electrodes provides information on the charge and composition of the metalndash;dielectric interface. The second harmonic light is created by the injection of surface polaritons onto the electrode surface via prism coupling techniques. A theory relating the second harmonic intensity to the square of the charge on the electrode successfully predicts the dependence of the SHG on applied voltage or potential and the time dependence of the SHG in response to a potential step. The time dependent second harmonic signal is also used to monitor the growth of a lead monolayer onto the silver electrode in the region of underpotential deposition.