Photoinduced amplification of the subharmonic of light in oxide glass

The parametric amplification of the radiation with fundamental frequency ha s been first observed by exposure of oxide glass to radiations with fundame ntal and doubled frequencies. The parametric amplification of signal is inv estigated both in the absence of the initial chi((2))-gratings and in the p resence of the initial photoinduced chi((2))-gratings in glass. Some proper ties of this amplification have been studied. An explanation of the observe d; process of parametric amplification that takes into account the coherent photogalvanic effect is presented. (C) 2000 Published by Elsevier Science B.V. All rights reserved.