Structure of the wave fields in a nondegenerate parametric ring oscillator

An investigation is reported of the structure of the eigenmodes of a parametric ring oscillator utilizing stimulated Brillouin scattering in a region of self-intersection of a signal light beam in a nonlinear medium. A study is made of the influence of nonreciprocity of a feedback loop, due to nondegeneracy of a four-wave interaction, on the lasing threshold and on the quality of optical phase conjugation near the threshold. It is shown that the phase conjugation quality and the structure of the scattered beam can be controlled by varying the coefficients representing spatial compression of the signal beam and the phase shift between the signal and scattered waves in the feedback loop.