中文摘要：

掺Tm3＋光纤激光器在工业、医疗、科技及军事领域具有重要应用前景。光纤布拉格光栅（FBG）是构成光纤激光器的重要元件。但掺Tm3＋光纤不具备光敏性,利用紫外脉冲激光很难在其中刻写FBG,即使采用增敏技术提高其光敏性,获得的FBG的折射率调制量也很小,尚不能满足应用要求,阻碍了掺Tm3＋光纤激光器全光纤化的发展。以相位掩模法的基本原理为基础,从理论上分析了以飞秒激光为刻写光源的技术要点,总结出与传统紫外激光刻写技术之间的差异及需要注意的问题。建立了飞秒激光相位掩模法刻写光纤光栅的实验系统,利用飞秒激光相位掩模法在非光敏光纤上刻写Bragg光栅,在非光敏掺Tm3＋硅基光纤上获得了衍射阶次为二的光纤Bragg光栅,并给出了显微镜下观察到的光栅结构。实验结果证明：飞秒激光可以将FBG刻写入非光敏性硅基光纤,并且具有成栅时间短的优点。

英文摘要：

Tm3＋-doped fiber lasers has an important application prospect in industrial,medical,scientific and military fields.Fiber Bragg grating（FBG） is an important component of fiber lasers.However,Tm3＋-doped silica fiber is not photosensitive.It is difficult to inscribe FBG into its core with UV-pulsed laser.The modulated quantity of refractive index of FBG obtained is too small to meet the application requirements,even if its photosensitivity is improved by the sensitization technology.It limits the all-fiber-based development of Tm3＋-doped fiber laser.Based on the basic principle of the phase mask method,the key technologies were analyzed theoretically when using femtosecond as inscribing source.Compared femtosecond laser inscription with traditional UV laser inscription,the existing differences and remarkable problems were summed up.The experimental setup for fiber Bragg grating inscription was built with femtosecond laser and a phase mask.A second-order FBG was inscribed into the non-photosensitive Tm3＋-doped silica fiber,and its structure was observed by an optical microscope.Experimental results show that the femtosecond laser can inscribe FBG in non-photosensitive silicon fiber,and has the advantages of a short time coming into the Bragg gate.