Experimental investigation of the fluctuations of the intensity of emission from a two-mode helium–neon laser

An experimental investigation was made of natural fluctuations of the intensity of the emission from a gas laser under two-mode conditions. The spectra of the random modulation of the intensity of the total output and of the individual oscillation modes were obtained and the mutual spectrum of the fluctuations of their intensities was determined. The measurements were carried out for different values of the ratios of die power outputs of the modes and at different levels of the total output. It was found that the behavior of the intensity fluctuations of the individual modes in the two-mode case differed considerably from the fluctuations in the single-mode case.