Dresden 2006 – scientific programme

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DF: Dielektrische Festkörper

DF 11: Electric, Electromechanical and Optical Properties II

DF 11.6: Talk

Friday, March 31, 2006, 12:50–13:10, M{\"U}L Elch

Suppression of optical damage in lithium niobate crystalsby thermo-electic oxidization* — •Matthias Falk, Theo Woike, and Karsten Buse — Physikalisches Institut, Wegelerstr. 8, 53115 Bonn

Lithium niobate crystals are a promising material for nonlinear optics. For applications, e.g. frequency mixing, undesired refractive index changes caused by intense light are a serious problem ("optical damage"). This effect originates from a light-induced redistribution of electrons between defect centers, a build-up of space-charge electrical fields, and finally the electro-optic effect. A method to suppress the optical damage is to remove all electrons, that occupy impurity sites and crystal defects, i.e. a perfect oxidization of the crystal is needed. We discovered a thermo-electric treatment, that provides an extremely strong oxidization of the crystals. Quantitative measurements of the optical damage are performed. Thermo-electrically oxidized crystals are much more robust than untreated crystals.

*Financial support of the DFG (FOR 557) and the Deutsche Telekom AG is gratefully acknowledged.