Magnetic Order of the Hexagonal Rare Earth Manganite Dy(0.5)Y(0.5)MnO3

TL;DR

This study investigates the magnetic ordering in the multiferroic Dy(0.5)Y(0.5)MnO3 using neutron diffraction, revealing complex phase transitions and a new magnetic phase diagram distinct from similar compounds.

Contribution

It provides the first detailed neutron diffraction analysis of Dy(0.5)Y(0.5)MnO3, uncovering unique magnetic phases and transitions not previously observed in hexagonal rare-earth manganites.

Findings

Magnetic order appears below 3.4 K on Mn and Dy sublattices.

Mn moments undergo a spin reorientation between 3.4 K and 10 K.

Antiferromagnetic order persists up to 70 K, with a distinct phase diagram.

Abstract

Hexagonal Dy(0.5)Y(0.5)MnO3, a multiferroic rare-earth manganite with geometrically frustrated antiferromagnetism, has been investigated with single-crystal neutron diffraction measurements. Below 3.4 K magnetic order is observed on both the Mn (antiferromagnetic) and Dy (ferrimagnetic) sublattices that is identical to that of undiluted hexagonal DyMnO3 at low temperature. The Mn moments undergo a spin reorientation transition between 3.4 K and 10 K, with antiferromagnetic order of the Mn sublattice persisting up to 70 K; the antiferromagnetic order in this phase is distinct from that observed in undiluted (h)DyMnO3, yielding a qualitatively new phase diagram not seen in other hexagonal rare-earth manganites. A magnetic field applied parallel to the crystallographic c axis will drive a transition from the antiferromagnetic phase into the low-temperature ferrimagnetic phase with little hysteresis.