Timing phase noise reduction of modelocked quantum-dot lasers by time-delayed optoelectronic feedback

A novel optoelectronic-feedback stabilisation scheme for passively modelocked semiconductor lasers is demonstrated. By electrical modulation of the absorber section with a signal directly obtained from the time-delayed optical laser output, a significant broadband reduction of timing phase noise (TPN) is achieved without the use of a reference oscillator. The similarity to TPN measurement results obtained by an all-optical feedback configuration suggests that the presented optoelectronic and the all-optical feedback configuration are based on a common underlying TPN reduction mechanism.