Formation of spiral ordering by magnetic field in frustrated anisotropic antiferromagnets

Abstract

We discuss theoretically phase transitions in frustrated antiferromagnets with biaxial anisotropy or dipolar forces in magnetic field applied along the easy axis at $T=0$. There are well-known sequences of phase transitions upon the field increasing: the conventional spin-flop transition and the flop of the spiral plane at strong and weak easy-axis anisotropy, respectively. We argue that much less studied scenarios can appear at moderate anisotropy in which the magnetic field induces transitions of the first order from the collinear state to phases with spiral orderings. Critical fields of these transitions are derived in the mean-field approximation and the necessary conditions are found for the realization of these scenarios. We show that one of the considered sequences of phase transitions was found in multiferroic MnWO${}_4$ both experimentally and numerically (in a relevant model) and our theory reproduces quantitatively the numerical findings.

6 pages, 2 figures

References in corpus (3)

• Helicity, anisotropies and their competition in a multiferroic magnet: insight from the phase diagram
• Cascades of phase transitions in spiral magnets caused by dipolar forces
• Spiral plane flops in frustrated helimagnets in external magnetic field

Cited by in corpus (5)

• Thermodynamically stable skyrmion lattice in tetragonal frustrated antiferromagnet with dipolar interaction
• Steady helix states in a resonant XXZ Heisenberg model with Dzyaloshinskii-Moriya interaction
• Phase competition in frustrated anisotropic antiferromagnet in strong magnetic field
• Ferromagnetic monolayer with interfacial Dzyaloshinskii-Moriya interaction: magnon spectrum and effect of quenched disorder
• Magnons in the fan phase of anisotropic frustrated antiferromagnets