INTENSITY CORRELATIONS OF MULTIMODE GAS-LASERS

We investigated the intensity correlation of a multimode Ar-ion laser. By the measurement of mode spectra and correlation times 20-30 simultaneously lasing modes, it was found that the behaviors of mode fluctuations are largely different between modes away from the center of a lasing line and modes near the center. These characteristics can be explained by the fluctuations caused by mode-mode coupling. Using third-order laser theory, we derived numerically the characteristics observed. We discuss the fitting curves of the correlation functions and the limit of the classical treatment.