Single-Cavity Three-Color All-Fiber Femtosecond Laser

In this letter, the design and characterization of an all-fiber femtosecond laser is reported that generates three wavelengths at 1030 nm, 1550 nm, and 1900 nm from a single cavity. The cavity is based on Er-doped fiber and it is mode-locked by a fiber coupled saturable absorber mirror. We take advantage of fiber optics nonlinearity to generate 1030 nm and 1900 nm wavelengths which can be amplified using well-known Yb-doped and Tm-doped amplifiers. The third output of the laser can be optimized to generate femtosecond pulses at a wide range of central wavelength from 1700 nm to 2000 nm. Since all three outputs of the laser are being generated from the same cavity, they can be easily synchronized to be used in various pump and probe applications. This approach reduces the size, power consumption and cost of the laser compared to three individual mode-locked cavities. The laser can be packaged in a 20 cm x 20 cm x 20 cm form factor.