Analysis of Self-Pulsating Sources Based on Cascaded Regeneration and Soliton Self-Frequency Shifting

We characterize the operation of self-pulsating sources made of two optical regenerators in cascade, namely a first regenerator of the type self-phase modulation spectral broadening and offset filtering, followed by a second regenerator of the type supercontinuum generation and offset filtering. The range of operation of this laser is explored as the wavelength and bandwidths of the band-pass filters are adjusted. We also provide experimental evidence that soliton self-frequency shift emanating from modulation instability triggers bursts of pulses at the repetition rate of the cavity. The stochastic nature of sources based on this concept leads to shot-to-shot pulse fluctuations in the cavity, which on average result in a flat supercontinuum extending beyond 1900 nm. Finally, a seed pulse can be sustained efficiently via this laser architecture, and the cavity consequently generates subpicosecond pulses at one of its output.