Effect of Zirconium Content on Defect Structure and Light Damage Resistance of Zr:Dy:LiNbO₃ Crystals

Abstract

In this paper, Zr:Dy:LiNbO3 crystals are prepared by traditional pull‐up method, in which Zr4+ doping concentrations are 0, 1, 2, and 4 mol%, respectively. In this paper, the defective structure of Zr:Dy:LiNbO3 crystals and their resistance to photodamage under different Zr4+ concentration doping are studied. Firstly, the influence of Zr4+ doping concentration on the defective structure of Zr:Dy:LiNbO3 crystal and the occupancy of doped ions under different Zr4+ concentrations are tested and discussed by infrared (IR) absorption spectroscopy and ultraviolet‐visible near‐infrared (UV–vis–NIR) absorption spectroscopy. The Judd–Ofelt theoretical analysis results show that when the concentration of doped Zr4+ is 2 mol%, the spectral quality factor (X) of Dy3+ in lithium niobate crystals is significantly improved compared with that of Dy3+ in other crystals. Secondly, resistance to photodamage of Zr:Dy:LiNbO3 crystals is studied and analyzed by the light scattering exposure energy flow threshold method. The results show that when the concentration of doped Zr4+ ions reaches 4 mol%, the exposure energy value is increased by 210 times compared with the no doping, which greatly improves the anti‐photodamage performance of the crystal.