Five orders cascaded Raman fiber laser oscillation from 1550nm to mid-ir at 2334nm wavelength

We demonstrate a cascaded Raman fiber laser (RFL) oscillation up to the 5-th order Stokes wave, from ~1550nm to mid-ir at 2334 nm, with silica fibers. The pumping was done with an amplified spontaneous emission (ASE) light of erbium-doped fiber (edf) in the 1550 nm wavelength regime. The low orders (1st to 3rd) could be easily obtained in continuous wave (CW) mode, while the 4th and 5th orders were obtained in a pulse mode. We used highly nonlinear fibers that allowed relatively short fiber cavity lengths of (10-100) m.