低对称性掺Yb氟氯化铅激光晶体的配位结构调控和性能研究

项目名称： 低对称性掺Yb氟氯化铅激光晶体的配位结构调控和性能研究

项目编号： No.61205171

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 信息四处

项目作者： 姜大朋

作者单位： 中国科学院上海硅酸盐研究所

项目金额： 25万元

中文摘要： LD泵浦掺Yb超快激光器具有结构紧凑、体积小、成本低、效率高、可重频工作等优点，是当前超强超短激光技术的前沿发展方向。但是，Yb离子属三能级系统，其激光下能级过于接近基态，存在自吸收、温度效应强和激光泵浦阈值偏高的缺点。本项目在Yb:CaF2、Yb:PbF2晶体的研究基础上，选择四方结构的氟氯化铅晶体（PbClF）作Yb离子的掺杂基质，利用低对称结构形成基态能级较大的Srark能级分裂，实现弱温度效应、低阈值的强耦合准四能级激光运转；另一方面，通过第一配位壳层阴离子配位结构的无序性（间隙F-或Cl-配位）增加Yb离子的吸收和发射光谱的宽带，有利于实现LD泵浦更短脉冲的飞秒激光输出。

中文关键词： Yb\Nd离子；低对称；团簇结构；Stark 劈裂；锁模激光

英文摘要： LD-pumped Yb-doped ultra-fast laser becomes the development cutting-edge of the ultra-short laser technology due to its compact structure, small size, low cost, high efficiency and re-frequency operation. However, there are also many shortcomings such as the self-absorption, the strong temperature effect and high pumping threshold because of its three-level system. On the basis of the research of Yb: CaF2, and Yb: PbF2 laser crystals, we select the tetragonal PbClF crystal as the laser host in this project whose low-symmetry structure can reduce to the larger Stark splitting of the ground state level, the weak temperature effect and quasi-four level laser operation with low threshold. On the other hand, the broad absorption and emission spectra of Yb ions can be obtained from the disorder of the first anion-coordination shell (interstitial F- or Cl-) due to the inhomogeneous broadening effect. This is conducive to the output of Yb femtosecond laser.

英文关键词： Yb\Nd ions；low symmetry；clusters；Stark splitting；mode-locked laser