Vortex Molecule in Unconventional Superconductor

Abstract

In this study we calculate numerically the vortex structure for a two-component Ginzburg-Landau functional in the regime when time-reversal symmetry is not spontaneously broken. In a wide range of parameters a single-quantum vortex dissociates into a bound pair (molecule) of half-quantum vortices. We determine the phase diagram of different types of vortices in the space of parameters of the Ginzburg-Landau functional. A novel characteristic length which is related to the vortex molecule size is found. The characteristic length is longer than the coherence length and shorter than the magnetic penetration length.