The vortex state (A-phase) of helimagnets Fe0.5Co0.5Si, MnSi, FeGe, as a continuous distribution of the dislocation density in the magnetic sublattice

Abstract

In this paper we propose to describe the deformed state of a helimagnet in the magnetic field (A-phase) with a pair of variables: the order parameter which characterizes the magnetic density and the tensor of distortion. Such description corresponds to discontinuities in the magnetic sublattice of the helimagnet accompanied by appearance of dislocations. It is shown that the phase diagram we found for the helimagnet is analogous to the phase diagram of the superconductors of second kind in the magnetic field, where the A-phase is a counterpart of the superconducting mixed state with the Abrikosov vortices.