The tunable two-wavelength fiber laser can be used as an ideal source for DWDM fiber com-munication and fiber sensor, because of its advantages such as wider bandwidth, narrower line-width and natural compatibility with fiber. A two-wavelength erbium-doped fiber ring laser has been designed and investigated experimentally, in which a tunable Y-type optical filter constructed with a pair of fiber Bragg gratings (FBGs) and a 3dB coupler have been used, and both FBGs are axially applied to different stres-ses to change both Bragg wavelengths so that a tunable two-wavelength laser output can be obtained. The experimentally obtained results have shown that the wavelength difference of the two-wavelength fiber la-ser is linearly tunable in a range from 0. 638 nm to 1.616 nm when the axial load varies from zero to 100 N, corresponding to a tuning sensitivity of 0.009 6 nm/N approximately. The fiber laser can be switch-able between one-and two-wavelength operations by adjusting the intra-cavity gains and losses via using the gain equalization method independently.%波长可调谐的双波长光纤激光器由于带宽较宽、线宽窄,与光纤元件天然兼容等特点,可作为DWDM光纤通信及光纤传感系统的理想光源.设计并实验研究了一种双波长环形腔掺铒光纤激光器,该激光器采用两根FBG和一个3dB耦合器构成可调谐Y型光滤波器,并通过对FBG施加轴向应力改变布拉格中心波长,从而获得波长可调谐的双波长激光输出.实验结果表明:当轴向负载在0～100 N范围内变化时,双波长光纤激光器的波长差在0.638～1.616 nm范围内线性调谐,调谐灵敏度为0.009 6 nm/N.利用增益均衡方法独立调节激光腔内的增益和损耗,光纤激光器可在单波长和双波长两种运转状态之间切换.
展开▼
