2μm波段超短脉冲因其是获得同步泵浦光参量振荡输出中红外飞秒激光的基础，同时在医学治疗、激光遥感和激光雷达等领域显示出广泛的应用而成为国内外的研究热点。本项目是基于2µm附近OPCPA系统，开发新的2 µm波段附近的种子光源来填补超短脉冲在2µm 波段的空白和不足。通过Tm3+和Ho3+共掺杂的激光介质，可以获得2μm波长的激光。无序晶体具有宽的吸收光谱和发射光谱，既有利于二极管泵浦，又有利于锁模脉冲产生；同时具有高的热导率，适合在大功率系统中应用。YCOB晶体结构具有一定的无序性，将Tm3+和Ho3+掺杂入YCOB晶体，通过非均匀加宽效应，可以进一步增宽晶体的发射波长范围，更有利于超短脉冲激光的产生。本课题拟采用提拉法生长Tm:Ho:YCOB晶体，并对其物理性能、2μm波段连续、脉冲和超短脉冲进行系统研究，将晶体生长、晶体物理及激光器优化设计相结合，为其实用化奠定基础。

The Ultrafast pulse in the 2-µm spectral range has become a hot research area because of its wide applications in medical treatment, laser remote sensing, laser radar etc. Additionally, it is also the foundation to obtain the mid-infrared femtosecond laser by the SPOPOP technique. This project will be to demonstrate the feasibility of the OPCPA system based on a novel seed laser sources in the 2-μm spectral range. The main objective will be to fill the gap in the 2-µm spectral range where short and ultrashort pulse solid-state lasers have shown only unsatisfactory performance or simply do not exist. With the Tm3+ and Ho3+ co-doped in the laser media, the tunable laser operation in the 2-μm spectral range can be achieved. The broad absorption and fluorescence spectra of the disordered crystal thus favor efficient diode pumping and ultrashort pulse generation. Additionally, compared with glass, the disordered crystal can also be used in the high power system because of the high thermal conductivity. The absorption and emission spectra of the Tm3+, Ho3+ co-doped YCOB crystal will be strongly inhomogeneously broadened due to the disordered lattice. The broad spectrum features a very efficient pumping and the production of ultrashort pulse. Characterization on Tm:Ho:YCOB crystal quality, thermal properties，optical properties and laser performance were carried out. The main objective will be to fill the gap in the 2-µm spectral range, to which it is a foundation for its practical application.