Dielecric characteristics of silica glasses and their relationship to SHG in poled silica

摘要

Electrical and dielectric relaxation measurements were conducted insilica glasses.Using the results of the measurements the casue of second harmonic generation (SHG) in thermally poled silica glass was considered.Absorption currents were measured as a function of time for various types of silica glasses and analysed using the theory of space charge polarisation.It was found that generation,annihilation,reproduction and temperature dependence of SHG in poled silica are similar to those of space charge polarisation.The fundamental parameters governing SHG in poled silica were found to be charge carrier concentration and mobility.Basedon the theory of space charge polarisation,and the experimental result of electrical relaxation,a method to increase the intensity of SHG is proposed.