Square Pulse and Harmonic Ultrashort Pulse Generation in Semiconductor Optical Amplifier-Based Mamyshev Oscillator

Modulation instability is responsible for the symmetry breaking of homogeneous spatio-temporal states or wave envelopes and the formation of stable patterns in a variety of physical media. Recently, by using this phenomenon in laser physics, remarkable developments have been made based on the use of the effect of self-phase modulation in Mamyshev oscillator [1-3]. The oscillator is designed using a spectral filter and a gain to compensate for filtering losses. By mismatching spectral filter offsets, entire cavity works as an element with the power-dependent transmission, suppressing the continuous wave lasing and favouring the formation of ultrashort pulses.