中文摘要：

对有源相移光纤光栅制成的非对称π-移分布反馈（DFB）光纤激光器的最佳耦合系数和相移位置及其输出特性进行了讨论，分别采用同向、反向2种泵浦方式从实验上进行了验证。制备的Er-Yb共掺有源相移光栅总长度为50mm，最佳耦合系数为150m^-1，最佳相移位置在29mm处。当980nmLD抽运功率为65mw时，在1549．42nm处实现了3mw的激光输出，斜率效率达到10％。连续开机工作2h以上，未观测到激光峰值波长漂移和自脉动现象。

英文摘要：

The optimal coupling coefficient value and phase-shift position of the distributed feedback（DFB） fiber laser made by active π-phase-shifted fiber grating were discussed, which were also demonstrated by experiments with co-pump and counter-pump configurations,respectively. An Er/Yb co-doped active phase-shifted fiber grating with an optimum grating length of 50 mm,coupling coefficient of 150 m^-1 and phase-shift position of 29 mm was fabricated. Under a LD pump power of 65 mW at 980 nm,a forward output power of 3 mW at 1549.42 nm was generated and the slope efficiency reached 10%. Meanwhile,during a 2 hours continuous operation, no phenomenon oflaser peak wavelength shifting or self-pulsing was observed.