Two-stage optical pulse compression for a mode-locking SOAFL driven by an asymmetric-duty-cycle square wave

► The proposed optical pulse compression technique is to improve the mode-locking SOAFL-based optical pulses with an externally-injected NRZ-like asymmetric-duty-cycle square-wave data stream in a more simple efficient way. All optical components used in the system are commercially available. ► The SPM effect on pulse jitter and pulsewidth in the optical pulse compressor cascaded by a DCF fiber and a SMF fiber is investigated empirically. We believe that it is a practical and useful work for this field. ► The linear compression of optical pulses by a DCF fiber for the first stage and the ninth-order soliton compression by a SMF fiber for the second stage are cascaded to narrow the optical pulse to 55 fs with a timing jitter of 0.45 ps. ► The two-stage pulse compression provides a time-bandwidth product up to 0.437 and a pulse-compressing ratio up to 54. The characteristic of the optical pulses can be improved by using commercially available optical components.