Switchable multiwavelength Erbium-doped fiber laser incorporating a sampled fiber Bragg grating written in polarization-maintaining fiber

摘要

A stable multiwavelength erbium-doped fiber laser is proposed and demonstrated successfully. Through carefully adjusting the state of the polarization controller, the stable two three-wavelength with a spacing of 0.8 nm and one four-wavelength with a spacing of 0.4 nm fiber laser have been obtained. A nonlinear optical loop mirror (NOLM) with 70-m long Photonic Crystal Fiber (PCF) is employed to ensure stable room-temperature multiwavelength operation. The measured power fluctuation of each wavelength is less than 0.2 dB and the peak power differences among the main oscillation wavelengths are less than 1.0 dB. Another desirable characteristic is that it needs a relatively low pump power of 100 mW. The signal-to-noise ratio is ～35 dB. And it is better than that inserting single-mode fiber (SMF) ever reported.