设计实现了一种基于SMS干涉结构的双波长掺铒光纤激光器。该激光器采用环形谐振腔,在环型腔内又包含了两个子腔,每个子腔内都包含一个作为滤波器的SMS干涉结构,通过调节可变光衰减器使其中一个子腔的损耗发生改变,进而可以使激光器在单波长与双波长两种工作模式之间自由切换。两种工作模式下的边模抑制比均大于36 dB。双波长状态下,把其中一个SMS干涉结构固定到恒温板上,当温度从30 ℃变化到190 ℃时,与该SMS干涉结构对应的激光器输出信号的中心波长从1550.3 nm变化到1556.8 nm,在此过程中,与另一SMS干涉结构对应的激光信号不受影响,中心波长也未发生改变,因此证实可以通过温度对波长间隔进行调谐。实验结果表明,这种激光器不仅具有结构简单、成本低的优点,还具有波长可开关和波长间隔可调谐的特性。

A dual wavelength erbium-doped fiber laser based on SMS interference structure was proposed. There were two sub-cavities in the ring cavity, and each SMS interference structure was used as a filter in each sub-cavity. The fiber laser could operate between the single wavelength mode and the dual wavelength mode by adjusting the variable optical attenuator to control the loss of a certain sub-cavity. The side mode suppression ratios of two modes were more than 36 dB. In dual wavelength mode, the center wavelength of the laser corresponding to the SMS interference structure above shifted from 1550.3 nm to 1556.8 nm, when the SMS interference structure was fixed on the constant temperature plate and the temperature changed from 30 ℃ to 190 ℃. The center wavelength of the laser corresponding to the other SMS interference structure did not shift, showing that the wavelength interval could be tuned by the temperature. The experiments show that the proposed fiber laser not only has the advantages of simple structure and low cost, but also has the characteristics of switchable wavelength and tunable wavelength interval.