Nonlinear Microwave Dynamics of Fractional Vortices in Two-Band Superconductors

Nonlinear $rf$ dynamics of composite Abrikosov vortices in two-band superconductors is considered in the framework of the elaborated phenomenological model. The possibility of dissociation of composite Abrikosov vortices with a whole magnetic flux quantum into fractional components under the influence of a rather strong microwave current is argued. The threshold for such kind of dissociation is calculated as a function of the microwave current amplitude and frequency. The possible manifestation of this type of vortex dissociation through the peculiarities of the amplitude dependencies of nonlinear surface resistance at different frequencies is considered.