Abstract

We have made a systematic investigation of the effect of reflecting light from one counterpropagating mode in a ring laser back into the other mode. In the experiment provision is made for retroreflecting a controllable fraction of the emerging optical field with variable phase back into the ring laser, while the two mode intensities, their fluctuations, and their cross-correlation are measured photoelectrically. The results of the measurements are compared to theoretical predictions based on the analytic solution of the Fokker-Planck equation in the steady state, and good agreement is found. In particular, we confirm that when the sum R₁ + R₂ is zero, where R₁,R₂ are complex backscattering coefficients, the laser behaves as if there is no backscattering in the steady state. (12 min)

© 1987 Optical Society of America