Channel-Spacing- and Wavelength-Tunable Multiwavelength Fiber Ring Laser Using Semiconductor Optical Amplifier

We have demonstrated a channel-spacing- and wavelength-tunable multiwavelength fiber ring laser based on a semiconductor optical amplifier and a tunable comb filter. By employing the comb filter, multiwavelength operation of up to 23 laser lines with the signal-to-noise ratio over 25 dB and 0.8-nm wavelength spacing was demonstrated at room temperature. The results show that the multiwavelength operation is even and stable. Furthermore, the shift of lasing wavelength and wavelength spacing were continuously controllable in this system