Investigation on the super-quadratic relation between second-harmonic generation intensity and poling voltage in SiO_2-GeO_2 thin films

摘要

Sol-gel method was used to prepare SiO_2-GeO_2 films. By investigating the second-harmonic generation (SHG) signal of the films after plate poling and corona poling, it was found that the SHG intensity of the samples increases with the plate poling voltage. A model of effective-dipole-inducing was proposed to explain the super-quadratic relation between the SHG intensity and the plate poling voltage.