Quasi-phase matching conditions induced by two-photon absorption in thermally poled glasses

Summary form only given. A second order susceptibility /spl chi//sup (2)/ is induced over /spl sim/10 /spl mu/m beneath the anodic surface in thermally poled fused silica. It is due to coupling of the /spl chi//sup (3)/ with a built in electric field E/sub int/ (/spl chi//sup (2)/-/spl chi//sup (3)/E/sub int/). Here, to achieve quasi-phase matching conditions (QPMC) in poled glasses, we propose a new method which within a couple or minutes results in the formation of both non-permanent linear index grating and permanent QPMC in poled glasses.