利用TSAG晶体磁光效应实现磁光调Q激光输出技术的研究

Magneto-optic materials have magnetic optical rotation effect, which can rotate the polarization direction of line polarized light passing through the magneto-optical material. This project aims to make use of magneto-optical effect of magneto-optical materials to develop an innovative magnetic and optical Q technology. The switching state of the oscillating laser in the resonant cavity is controlled by the magneto-optical effect of magneto optic materials, and the output of Q modulation laser is realized. TSAG crystal has excellent magnetic and optical properties and stable physical and chemical properties, besides, large size and high quality crystals is easy to be grown. In this project, high quality TSAG and Nd:TSAG crystals will be prepared and characterized on the basis of previous work. The Q switched laser experiment device will be designed and built. The property of Q switched laser will be evaluated by LD pump, and the magneto-optic Q switch mechanism and technology would be explored. The integrated technology of Nd:TSAG crystal Q switching device integration will be carried out to realize the self-tuning Q switched laser output. The Q-switch technology is widely used to generate short pulse and large energy laser. Therefore, this project not only has innovative scientific significance, but also has a wide range of application prospects.

磁光材料具有磁致旋光效应，能使穿过磁光材料的线偏振光偏振方向发生旋转。因此，本项目基于磁致旋光效应尝试提出磁光调Q技术：利用磁光材料的磁光效应来控制谐振腔中振荡激光的开关状态，实现调Q激光输出。TSAG晶体具有优异的磁光性能和稳定的物理化学性质，本项目拟以TSAG作为磁光晶体进行磁光调Q技术研究。制备高质量TSAG和Nd:TSAG晶体，表征晶体性能；设计和搭建磁光调Q激光实验装置，采用LD泵浦评估调Q激光性能，探索出磁光调Q机制和技术；开展Nd:TSAG晶体调Q器件一体化技术研究，实现磁光自调Q激光输出。通过调Q技术可以产生短脉冲、大能量激光。本项目的开展不仅具有创新性的科学意义，也具有广泛的应用前景。

本项目的研究内容及结果主要包括以下几个部分：1）针对铽钪铝石榴石磁光晶体容易开裂的问题，从原料制备和晶体生长温场梯度两个方面开展工作，获得最佳组分配比、高温固相法合成原料工艺、超低温度梯度温场模块设计，实现了大尺寸高质量TSAG、TLSAG和NdTSAG的提拉法生长，TSAG和TSLAG晶体尺寸达到Ø 65 mm × 70 mm，Nd:TSAG达到 Ø 50 × 100 mm，为激光实验提供晶体材料基础。2）开展晶体结构、热学、磁光、光谱性能测试，为后续激光实验磁光晶体元件加工和泵浦确定方向，明确晶体元件长度尺寸，泵浦波长、发射波长、磁场强度大小，相关设计提供参数。3）开展晶体元件加工、磁场搭建、谐振腔设计等研究工作，为激光实验建立实验条件。.科学意义：本项目的开展攻克了大尺寸铽钪铝石榴石磁光晶体容易开裂的问题，为新一代磁光材料的应用奠定晶体生长技术基础，同时提供了新的调Q技术，丰富了调Q激光实现途径。