Raman-assisted UV generation in KTP frequency doublers

Summary form only given. An attempt to lase a Raman line in a KTP doubler aroused our suspicions that the Raman process might be implicated in KTP damage. Although occasional flashes of directed Stokes light were observed, they were invariably self-terminating and associated with bulk crystal catastrophic damage. We therefore explored the possibility that Raman-shifted light generated in the doubling process was phase matched to produce damaging UV.<
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