Abstract

Experiments have shown that the output of semiconductor lasers can exhibit mode hopping between two longitudinal modes. Although the total output power remains constant, the power in one mode will switch cleanly between two values, with the time between switches varying randomly. The average dwell times in each state have been observed to be functions of the ratio of the time-averaged powers of the two modes. A theory based on a first passage time formalism is applied to calculate this dependence in two-mode semiconductor lasers. Beginning with the coupled Lamb equations for a two-mode laser, the solution of a Fokker-Planck equation yields analytic results for the mode intensity averages. Average vs dwell times are calculated from the average first passage time between states for one mode. Analytic results for the average relative mode intensities vs dwell times are compared with experimental data for a semiconductor laser.

© 1991 Optical Society of America