Abstract Based on the thermodynamic analysis of oxygen vacancy defects in lithium niobate (LiNbO3 (LN)) and the data of thermogravimetric experiment, the formation enthalpies of congruent and several rare-earth (RE) doped LN crystals have been calculated. It was found that the formation enthalpy of oxygen vacancies can be decreased evidently by doping with valence-changeable RE ions. The experimental results were discussed and a new reduction process for photorefractive LN crystals at a relatively low temperature was proposed, and the reduction-treated crystals showed good effect in practical use.
Received: 30 June 1992
Revised: 15 November 1992
Accepted manuscript online:
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