20 GHz transform-limited optical pulse generation and bit-error-free operation using a tunable, actively modelocked Er-doped fibre ring laser

The authors report the generation of 20 GHz, 3.0-3.5 ps transform-limited optical pulses across the wavelength tunable range 1550-1557 nm using a wavelength tunable, polarisation-maintaining actively modelocked Er/sup 3+/-doped fibre ring laser. Stable bit-error-free modelocking operation is confirmed throughout the wavelength tuning range.<>