Neutron diffraction in MnSb2O6: Magnetic and structural domains in a helicoidal polar magnet with coupled chiralities

Abstract

MnSb${}_2$O${}_6$ is based on the structural chiral $P$321 space group #150 where the magnetic Mn${}^{2+}$ moments ($S=5/2$, $L\approx 0$) order antiferromagnetically at $T_{\mathrm{N}}=12$ K. Unlike the related iron based langasite (Ba${}_3$NbFe${}_3$Si${}_2$O${}_{14}$) where the low temperature magnetism is based on a proper helix characterized by a time-even pseudoscalar `magnetic' chirality, the Mn${}^{2+}$ ions in MnSb${}_2$O${}_6$ order with a cycloidal structure at low temperatures, described instead by a time-even vector `magnetic' polarity. A tilted cycloidal structure has been found [M. Kinoshita et al. Phys. Rev. Lett. 117, 047201 (2016)] to facilitate ferroelectric switching under an applied magnetic field. In this work, we apply polarized and unpolarized neutron diffraction analyzing the magnetic and nuclear structures in MnSb${}_2$O${}_6$ with the aim of understanding this magnetoelectric coupling. We find no evidence for a helicoidal magnetic structure with one of the spin envelope axes tilted away from the cycloidal $c$-axis. However, on application of a magnetic field $\parallel$ $\vec{c}$ the spin rotation plane can be tilted, giving rise to a cycloid-helix admixture that evolves towards a distorted helix (zero cycloidal component) for fields great than $\approx$ 2 T. We propose a mechanism for the previously reported ferroelectric switching based on coupled structural and magnetic chiralities requiring only an imbalance of structural chiral domains.

References in corpus (16)

• Spin current and magneto-electric effect in non-collinear magnets
• Ferroelectricity in spiral magnets
• Multiferroic materials and magnetoelectric physics: symmetry, entanglement, excitation, and topology
• Magnetic inversion symmetry breaking and ferroelectricity in TbMnO3
• Critical exponents and equation of state of the three-dimensional Heisenberg universality class
• Single domain magnetic helicity and triangular chirality in structurally enantiopure Ba3NbFe3Si2O14
• Parity Broken Chiral Spin Dynamics in Ba${}_3$NbFe${}_3$Si${}_2$O${}_{14}$
• Magnetic chirality as probed by neutron scattering
• Helical spin-waves, magnetic order, and fluctuations in the langasite compound Ba3NbFe3Si2O14
• MnSb2O6: A polar magnet with a chiral crystal structure
• Helical bunching and symmetry lowering inducing multiferroicity in Fe langasites
• Experimental magnetic form factors in Co3V2O8: A combined study of ab initio calculations, magnetic Compton scattering and polarized neutron diffraction
• Magnetic anisotropy and the phase diagram of chiral MnSb2O6
• Lattice and magnetic dynamics in polar chiral incommensurate antiferromagnet Ni${}_2$InSbO${}_6$
• Imitation of spin density wave order in Cu${}_3$Nb${}_2$O${}_8$
• Spin-wave directional anisotropies in antiferromagnetic Ba${}_3$NbFe${}_3$Si${}_2$O${}_{14}$

Cited by in corpus (2)

• Kinetomagnetism of chirality and its applications
• Neutron scattering sum rules, symmetric exchanges, and helicoidal magnetism in MnSb${}_2$O${}_6$