Theoretical and experimental analysis of the complex dynamics of the spectral amplitude of noise-like pulses

Noise-like pulses (NLPs) are ultrashort light pulses that are generated through the mode-locked regime. Using this regime, it is possible to generate several ultrashort light pulses with different properties. NLPs have the characteristic that their electric field has a very complex distribution, and their envelope is very easy to tune into several shapes by modifying the polarization of the laser light inside the cavity. The laser that produces NLPs can operate in a stationary mode: in this mode of operation, the properties of the NLPs remain constant, and in a non-stationary mode: in this mode of operation the properties of the NLPs change with each trip into the cavity. In this paper, we present a theoretical and experimental analysis of the maximum value of the spectral amplitude of the NLPs when the cavity operates in a stationary mode. The experimental measurements of the spectral amplitude of the NLPs were compared with the theoretical model of light intensity transmission based on Jones matrices and with the theoretical model of the NOLM. We analyze NLPs with a wavelength carrier of 960 nm, a repetition rate of 60 MHz, and a temporal profile with a duration in the order of nanoseconds. The cavity with which we generate the NLPs is a figure-eight fiber laser.