中文摘要：

提出和验证了一种L波段双波长掺铒光纤激光器（EDFL）双稳态控制变换和双波长开关切换的方法．将偏振控制器（PC）插入基于3dB光纤耦合器的光纤环镜（FLM）中，并将该FLM用作L波段双波长级联线形耦合腔EDFL的公共腔镜，结果表明，调节PC可以改变FLM的反射率，实现对EDFL双稳态特性的有效控制，且双稳态特性随FLM反射率呈单调变化．利用这一性质，提出并证实。对于处在FLM最大反射率对应的双稳态第一跃变点和最小反射率对应的双稳态第二跃变点之间的任意固定抽运光功率，调节PC可实现两个稳态之间的相互变换和双波长之间的相互切换．

英文摘要：

A technique for controlling and mapping the optical bistability of an L-band dual-wavelength erbium-doped fiber laser （EDFL） with cascaded linearly coupled cavities was presented and demonstrated in this paper. By using a fiber loop mirror （FLM） with a polarization controller （PC） in the loop as the common mirror of the laser, we found that the bistability of the laser may be efficiently controlled by adjusting the reflectivity of the FLM which is determined by the PC state. Moreover, the bistability varies monotonically with the reflectivity of the FLM. By making use of this property, the two stable states and the two potential lasing wavelengths of the laser may be respectively mapped and switched with respect to each other by adjusting the PC for any fixed pump powers, as long as the pump power lies between the first turning point of the bistability for the maximum reflectivity of the FLM and the second turning point of the bistability for the minimum reflectivity of it.