The magnetic structure of DyFeO3 revisited: Fe spin reorientation and Dy incommensurate magnetic order

High resolution and high intensity neutron powder diffraction is used to study the ground state magnetic order and the spin reorientation transition in the orthoferrite DyFeO3. The transition from the high temperature k = 0 Gamma(4) (G ( x ) A ( y ) F ( z )) to the low temperature Gamma(1) (A ( x ) G ( y ) C ( z )) type order of the Fe-sublattice is found at T (SR) = 73 K and does not show any thermal hysteresis. Below T (N2) = 4 K the Dy-sublattice orders in an incommensurate magnetic structure with k = [0, 0, 0.028] while the Fe-sublattice keeps its commensurate Gamma(1) type order. DyFeO3 is the first orthoferrite RFeO3 to possess an incommensurate magnetic order of the rare earth sublattice under zero field conditions; an important piece of information neglected in the recent discussion of its multiferroic properties.

Automated summary

We used high resolution and high intensity neutron powder diffraction to study the magnetic order and spin reorientation transition in orthoferrite DyFeO3. We found that at low temperatures, the Fe-sublattice shows a Gamma(1) type order while the Dy-sublattice exhibits an incommensurate magnetic structure. This is an important finding in DyFeO3, which has been overlooked in recent discussions on its multiferroic properties.