激光加热基座法生长高质量Yb^(3+)掺杂Y_(3)Al_(5)O_(12)单晶光纤

Growth of High-quality Yb^(3+)-doped Y_(3)Al_(5)O_(12) Single Crystal Fiber by Laser Heated Pedestal Growth Method

单晶光纤即具有光纤形态的单晶材料,是功能晶体材料一维化发展的重要体现。单晶光纤兼具单晶材料优异的光学性能和激光光纤散热效率高、光束质量高等特点,有望解决传统玻璃材质激光光纤非线性效应强、热导率低等瓶颈问题,实现激光峰值功率、脉冲能量等性能的突破。本工作采用自主研制的激光加热基座(Laser-heated Pedestal Growth,LHPG)单晶光纤炉制备了两组Ф0.2 mm×710 mm的Yb^(3+)掺杂Y_(3)Al_(5)O_(12)(Yb:YAG)单晶光纤,并对其进行了表征。制备的单晶光纤长径比大于3500,直径波动小于5%,且表现出一定的柔韧性;X射线摇摆曲线测试结果显示Yb:YAG单晶光纤的结晶质量与所用源棒相比有所提升;EDS线扫描结果证明单晶光纤中的Yb3+沿轴向呈现均匀分布。实验结果表明:准一维化的单晶光纤具有良好的结晶质量与光学均匀性,有望成为一种性能优异的高功率激光增益材料。

Single-crystal fiber(SCF)is a fiber-shaped monocrystalline material,which is an important tendency for the development of low-dimensional functional crystals.Combining the excellent optical properties of bulk crystals and the high-efficient thermal dissipation as well as the high beam quality of optical fibers,SCFs are believed to solve the bottlenecks of conventional laser fibers such as unfavorable non-linear effects and poor thermal conductivities,can thus achieve higher laser peak powers and pulse energy.Here,we describe the results of synthesis and characterization of two Yb^(3+)-doped Y_(3)Al_(5)O_(12)(Yb:YAG)SCFs(Ф0.2 mm×710 mm),which were grown by a selfdeveloped laser-heated pedestal growth(LHPG)apparatus.The prepared SCFs possess a length-to-diameter ratio greater than 3500,a diameter fluctuation less than 5%,and show high flexibility for bending.The analysis of X-ray rocking curve indicates that the crystallinity of the grown SCF is improved compared with that of the source rod.The EDS line scan shows that the Yb^(3+) ions are uniformly distributed along the axial direction.Results of these characterizations of SCFs indicate that SCFs maintains excellent crystallinity and high optical homogeneity,showing promising candidate for high-power laser applications.