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High resistance against ultraviolet photorefraction in zirconium-doped lithium niobate crystals.

The UV photorefraction of Zr-doped lithium niobate (LN:Zr) was investigated. The experimental results show that LN:Zr crystals have high resistance against photorefraction in the UV region as well as in the visible range and can withstand a UV light intensity of above 10(5) W/cm(2). According to the fitting results of erasing curves with UV and green light, a two-center O(2-/-)-defect model was suggested. Our results indicate that LN:Zr is an excellent candidate for optical damage resistance from the UV to the visible spectrum.