Optical damage inhibition and thresholding effects in lithium niobate above room temperature

High-intensity single-beam photorefractive data on LiNbO3 show the occurren ce of a well-defined intensity threshold for enhanced deterioration (fannin g) of the output beam. That threshold markedly rises with temperature in th e range 20-160 degrees C. Below threshold, the beam profile is only slightl y modified during propagation and it remains essentially independent of the Light intensity. These results offer relevant information on beam degradat ion in applications involving high light density powers. The data indicate that the thresholding effect is thermally activated with an activation ener gy of 0.24 eV within the range of values found for the photoconductivity. ( C) 2000 Elsevier Science B.V. All rights reserved.