Polarisation interactions in birefringent fibre waveguides with anisotropic Kerr nonlinearity

The influence of the antisymmetric components of the fourth-rank nonlinear susceptibility tensor is taken into account in considering the polarisation self-interaction of waves in birefringent fibre lightguides. The effects discussed include the appearance of an instability of a linearly polarised mode with a lower propagation velocity, formation of a nonlinear mode with elliptic polarisation, and selfrotation of the plane of polarisation of linearly polarised light.