Broadening of spectral modes of a semiconductor laser in the case of pulsations of the emission intensity

The process of spectral broadening of longitudinal modes of a semiconductor laser in the presence of pulsations of the emission intensity was investigated experimentally. A theoretical analysis was made of the influence of oscillations of the electron density on the optical length of the resonator and, consequently, on the longitudinal mode wavelengths. The limit cycle in the phase plane calculated for deep pulsations was compared with the experimentally measured phase trajectory.