Abstract

We study the mechanism of second harmonics generation in lead silica scanned with an electron beam. Firstly, we found to use a-beam irradiating on either silica or lead silica there is not any second harmonic signal. The electric field in the layer can not be produced by positive particle. Secondly we change lead component, 47%, 51%, 61% and 71% by using F₂, SF₂, SF₁₁, and ZF₇ lead silica, respectively. The second harmonic signal increases linearly with the lead ratio. Thirdly we found there is a saturated signal at an optimum scanning values of total electron charge. This is due to the threshold of inner electric field beneath the glass surface to cause breakdown. Fourthly we obtain the coefficients for Bohr-Bethe electron penetration formula in lead silica.

© 1997 Optical Society of America