Effect of strain on laser damage and its relation with precursor defects in KDP/DKDP

This paper reports a study on correlation between stress field generated by extensive crystalline defects such as dislocation or growth boundaries and laser damage. It is found that stress fields decrease laser damage resistance. This result is compatible with the hypothesis that laser damage precursors consist of clusters of punctual defects. Indeed, such defects are affected by stress fields as their concentration varies in order to minimize the free energy of the crystal. Chemical analysis carried out on one of the crystal tend to show that the punctual defects involved are intrinsic rather than extrinsic.