The effect of an intracavity accelerating dielectric on the frequencies of counterpropagating waves in a ring laser is calculated and measured. These circulating waves, which are neither harmonic nor propagating in a direction parallel to the motion of the dielectric, have their frequencies determined by the phase velocity in the dielectric. For a nonaccelerating dielectric, the effect of the transverse drag on the frequencies of the counterpropagating waves is measured.

• Received 26 May 1992

DOI:https://doi.org/10.1103/PhysRevA.48.1082