Stable and wideband wavelength-tunable actively mode-locked fiber ring laser using a short length bismuth-oxide-based erbium-doped fiber and a short length bismuth-oxide-based highly nonlinear fiber

We demonstrate an actively mode-locked fiber ring laser employing a 151-cm-long bismuth-oxide-based erbium-doped fiber (Bi-EDF) and a 250-cm-long bismuth-oxide-based highly nonlinear fiber (Bi-HNLF). The cavity length is as short as 10 m because of these short fibers. A 60-nn wavelength tuning from 1535 nm to 1595 nm can be achieved by utilizing the wide gain bandwidth of the Bi-EDF. Since the Bi-HNLF has a very high nonlinear coefficient y of 1100 W^-1km^-1, the supermode noise can also be reduced sufficiently. Thus, stable and clean short pulses with a repetition rate of 10 GHz can be successfully generated over the entire wavelength tuning range covering both the C- and L-bands.