How Does Thermal Poling Affect the Structure of Soda-Lime Glass?

Abstract

Soda lime glasses polarized either with an open or a blocking anode have been characterized by IR reflectance spectroscopy and a combined analysis of second harmonic generation and Raman imaging. The experimental results clearly show that the electrode nature influences strongly (i) the thickness of the space charge layer, (ii) the χ (2) efficiency, and (iii) the structural rearrangements. Besides, using theoretical models accounting for charge carriers' mobilities, the respective influence of two distinct compensation mechanisms, that is an injection of positive charges (H 3 O + /H + ions) or a drift of oxygen ions, have been confirmed.

Measurement of the refractive index of electrically poled soda-lime glass layers using leaky modes

“…Electrically poled glass has received considerable interest in the literature in recent years, not least due to the observation of a second order non-linearity in its refractive index [1][2][3][4][5]. These effects have been observed in many glasses including silica glass and soft soda-lime and borosilicate glasses [1][2][3][4][5].…”

“…These effects have been observed in many glasses including silica glass and soft soda-lime and borosilicate glasses [1][2][3][4][5]. There have, however, been other applications of electrically poled glasses in the literature.…”

“…It is generally accepted that poling of glass with a large applied electric field results in the formation of a region beneath the anode that is depleted of Na + , K + and other mobile positive ions [5,[18][19]. Due to the removal of these, a negative space charge develops in the poled region.…”

“…For so called blocking anodes, which cannot inject neutralizing positive ions, the applied voltage is dropped across the narrow space charge region thus creating a large electric field. This high field encourages the motion of non-bridging O -ions towards the anode [5,18]. In the other extreme for non-blocking anodes, the injection of H + and OH3 + ions from the atmosphere can occur [20].…”

“…These replace the Na + and K + ions that have vacated the poled glass region in a process similar to electric field assisted ion exchange. However, even with this type of anode there is evidence that some oxygen ion motion can occur under certain poling conditions [5].…”