【摘 要】
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Ce-doped lithium niobate (LiNbO_3) single crystals were grown from the melts with various Li/Nb molar ratios (0.750,0.850,0.946,1.100,1.250 and 1.380) by Czochr
【机 构】
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Department of Applied Chemistry
论文部分内容阅读
Ce-doped lithium niobate (LiNbO_3) single crystals were grown from the melts with various Li/Nb molar ratios (0.750,0.850,0.946,1.100,1.250 and 1.380) by Czochralski method,while doping concentration of Ce was 0.1 mol%. Infrared spectra (IR) and Ultraviolet-visible absorption spectra (UV) of the crystals were measured to investigate the location of Ce ions and defect structure in crystals. The writing time,erasing time,photorefractive sensitivity and dynamic range were measured by two-wave coupling equipment. The results showed that Ce takes the place of Li lattice site,and the LiNbO_3 crystal grown from the melt with Li/Nb ratio of 1.250 is stoichiometric crystal,which has the best properties due to the synergistic effect of Ce ion and Li/Nb ratio. Also the influence of various Li/Nb ratios on the defect structure and optical properties of the crystal was reported.
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