Modeling of the second harmonic generation in SiO2 sol–gel films doped with nanoscopic DR1 molecules as function of the poling time

A physical description for the second harmonic generation (SHG) intensity as function of corona poling time in SiO2:DR1 sol–gel films is shown. This model describes the poling time dependence of the SHG based on a damped oscillator description of the nanomolecules of DR1. Instead of an usual biexponential or polynomial model with meaningless parameters, all the parameters from our model have a physical interpretation. The model results have been experimentally verified in several SiO2:DR1 sol–gel films with different side-chain doping concentrations.