Investigation of room-temperature multiwavelength fiber ring laser that incorporates an SOA-based phase modulator in the laser cavity

A theoretical and experimental study of a multiwave-length fiber-ring laser that incorporates a semiconductor optical amplifier (SOA) in the laser cavity as a phase, modulator to suppress the homogeneous line broadening is presented. The analysis reveals that the phase shift introduced by the SOA-based phase modulator is more significant than that formed using a LiNbO3 phase modulator, which leads to a better suppression. of the homogeneous line broadening. Multiwavelength lasing with small wavelength spacing and improved stability at room temperature is achieved. A fiber-ring laser based on the proposed approach is implemented. Stable, multiwavelength operation with up to 26 wavelengths and wavelength spacing as small as 0.19 nm at room temperature is demonstrated.