晶场调制宽带吸收的掺镨钆镓石榴石橙黄光激光晶体生长与性能研究

The orange-yellow laser have widely promissing applications in the laser commuication, atmospheric remote sensing, laser display fields, and so on. Currently, the mainly methods to achieve this range laser are dual-wavelength frequency and raman frequency shift, the laser systems are complicated and limits them no more wildly applications. Recently, with the development of blue laser diodes, all-solid-state orange-yellow lasers have new developing opportunities, which are suitable for widely applications. However, the Pr3+-doped fluoride can’t meet the widely application requirements due to their poor physical and chemical performance. Thus, exploring excellent laser oxide materials becomes the key issue in the present. Pr：GGG have excellent orange-yellow luminescence properties and strong blue absorption, but its absorption band is too narrow,which is unfavourable for the improvement of the pumping efficiency. In this project, the crystal field can be modified by substituting the host with some Ca2+，Mg2+，Zr4+ ions, which can widen the absorption band, be beneficial for the LD pumping and improve the absorption efficiency. We will study the crystal growth, optical and structure properties, crystal field to optimize substituting ratio and the doped ions concentration and search for the law of the absorption band broadening. We also explore the influence scheme of the phonon and cross-relaxation to the optical and laser performance, which can establish the Pr3+ doped oxides application foundation for all-solid-state orange-yellow laser.

橙黄光激光在激光通信、大气遥感、激光显示等领域有广泛应用前景。目前实现该波段激光输出的双波长和频及拉曼频移系统结构复杂，限制了其应用领域拓展。近年来随着蓝光LD的不断发展，适于广泛应用的全固态橙黄光激光器也迎来了新的发展机遇。但是具有优良光谱和激光性能的掺镨氟化物材料因物化性能不佳不能适应其广泛应用的发展需求，因此探索优性能橙黄光氧化物激光材料成为关键。Pr:GGG具有良好的橙黄光发光性能，在蓝光波段有强吸收，但吸收带较窄，不利于LD泵浦效率的提高。本项目通过掺入Ca2+、Mg2+、Zr4+替代离子，调节晶场，展宽Pr3+吸收带宽，使之更利于LD泵浦，提高泵浦效率。通过晶体的生长、光谱、结构、晶场参数研究，寻求最佳的替代离子掺入比例和Pr3+掺杂浓度以及吸收带展宽规律。探索声子、交叉弛豫等对光谱及激光性能影响的机理，为掺Pr3+氧化物晶体的全固态橙黄光激光应用奠定基础。

橙黄光激光在激光通信、大气遥感、激光显示等领域有广泛应用前景。本项目围绕展宽Pr3+离子吸收带宽和实现LD泵浦激光晶体获得橙黄光激光输出的研究目标，开展了Pr3+掺杂GGG、(Ca,Mg,Zr)GGG、YAG，Dy3+掺杂YAG、GdScO3，Er3+掺杂GdTaO4、GYSGG等晶体的生长和光谱性能研究工作，设计并搭建了LD泵浦的可见光激光实验系统，研究了Pr3+吸收带宽随GGG基质组分的变化规律，解释了基质声子、交叉驰豫等对Pr3+掺杂晶体可见光光谱及激光性能的影响。本项目取得了较为重要的研究结果和数据，具有一定的科学意义：.1）获得了GGG中较优的Pr3+掺杂浓度和Ca、Mg、Zr的替代比例以及Pr3+离子吸收带的展宽规律；制备出了优质Φ32mm×85mm的Pr:GGG、Pr:(Ca,Mg,Zr)GGG晶体，基质掺杂后Pr3+在450nm附近的吸收带宽由2nm展宽至3.4nm，有效提高了吸收效率。这一结果为提高稀土离子吸收效率和激光泵浦效率提供了新的思路和科学依据，为实现高效橙黄光激光输出及其应用奠定了良好基础。.2）筛选出了Dy3+、Er3+作为新型可见光激活离子，优选并生长出了高质量的Dy3+掺杂YAG、GdScO3，Er3+掺杂GdTaO4、GYSGG可见光晶体。在国内首次采用450nm LD泵浦Dy:YAG晶体实现了平均功率56mW、最大单脉冲能量1.1mJ的黄光激光输出，光光转化效率为4%，斜效率为5%。这可进一步推动其在激光通信、大气遥感、激光显示、生物医学、材料科学、超高清晰度打印和扫描等领域的应用。.3）理论分析了Pr:YAG晶体的低温吸收光谱，获得了Pr3+离子能级结构和晶场参数，解释了基质声子、交叉驰豫等对Pr3+掺杂晶体可见光光谱及激光性能的影响，为Pr3+掺杂晶体激光系统的设计和实验方案优化改进提供了参考。