Broadband tunable all fiber laser at 2 μm band

An all-fiber tunable fiber laser with 2 μm band based on Fabry-Perot (F-P) fiber filter was designed and demonstrated experimentally. An amplified 1 550 nm semiconductor laser was adopted to pump a segment of Tm-Ho co-doped fiber (THDF), and then the optical gain at 2 μm band was obtained. The results indicate that the tuning range, linewidth and side-mode suppression ratio of the output laser are 195 nm, 0.05 nm and 66.98 dB, respectively. The whole structure adopts the THDF amplification structure, which can achieve output power of watt level.