A Novel Switchable and Tunable Dual-Wavelength Single-Longitudinal-Mode Fiber Laser at 2

Abstract

A switchable and tunable dual-wavelength single-longitudinal-mode (SLM) fiber laser in a 2-μm region based on saturable absorber and self-injection locking is proposed and experimentally demonstrated. The laser topology is based on the parallel connection of fiber Bragg gratings (FBGs) using a coupler to realize switchability and tunability by adjusting the cavity losses and the center wavelengths of FBGs, respectively. The saturable absorber and the self-injection locking ensure the stable operation of the laser at SLM. Dual-wavelength with the power-instability of ~0.7 dB, the wavelength drift of ±0.08 nm, and a tuning range of 6.7 and 2.7 nm is obtained. Stable SLM operation with linewidths of <;9.1 MHz analyzed by the self-homodyne method is obtained. The proposed configuration has ingenious and compact structure and reliable performance, and will have promising applications in the fields of multiparameter detection in gas sensing or new wavelength-division-multiplexing (WDM) communication systems.