STATIONARY MIXED-POLARIZATION SPATIAL SOLITONS AND THEIR STABILITY INSEMICONDUCTOR WAVE-GUIDES

Coupled nonlinear Schrodinger equations are used to describe propagati on in the presence of an anisotropic Kerr nonlinearity in the most com mon semiconductor waveguide configuration. Stationary soliton solution s are identified analytically for the single-polarization case and num erically for the mixed-polarization case. The stability of these stati onary solutions is assessed by using a linear stability analysis. Anal ytic forms for the bifurcation points are given, where the single-pola rization state becomes unstable and the mixed-polarization state emerg es. A new form of polarization instability is also identified where th e ''fast'' mode soliton becomes unstable to antisymmetric perturbation s at low power. Numerical studies are used to confirm the linear stabi lity analysis results. [S1063-651X(98)02411-8].