We have proposed and demonstrated a nonlinear polarization-rotation-based fiber laser with two different operation states: passive mode-locking and multiwavelength emission. The intensity-dependent transmission or loss induced by nonlinear polarization rotation accounts for the distinct operation regimes. Our experiment results indicate that both passively mode-locked pulses and continuous-wave multiwavelength can be generated from the same fiber laser just through adjusting polarizations. Another characteristic of the current multiwavelength laser is that the used periodic filter is a birefringence fiber filter, which facilitates all-fiber integration of the fiber laser, so it is a potential multifunction laser source with all-fiber configuration and convenient manipulation.
Zhang, Z. X., Xu, K., Wu, J., Hong, X. B., & Lin, J. T. (2008). Two different operation regimes of fiber laser based on nonlinear polarization rotation: passive mode-locking and multiwavelength emission. IEEE Photonics Technology Letters, 20(12), 979-981. https://doi.org/10.1109/LPT.2008.923549