Magnetooptic effects in a YAG:Nd3+ ring laser with a nonplanar resonator

An experimental investigation was made of the influence of the Faraday and Zeeman effects on the operation of a YAG:Nd³⁺ ring laser with a nonplanar resonator. The opposite waves were decoupled by a polarization-frequency method and an unusual lasing regime was observed: in this regime one of the waves had the circular polarization and the opposite one was linearly polarized. The magnetooptic effects could be used to establish different transverse structures of the opposite-wave fields. Magnetooptic modulation was used to switch the direction of emission from the laser avoiding transient processes at a relaxation frequency. A magnetooptic feedback based on the difference between the intensities of the opposite waves resulted in a considerable reduction in the concurrent attenuation and established a beat regime in a wide range of the frequency splitting between the opposite waves. Variation of the feedback parameters of the laser resulted in a strong hysteresis and produced bistable states.