4f spin driven ferroelectric-ferromagnetic multiferroicity in PrMn2O5 under a magnetic field
Résumé
In contrast to all other members of the RMn2O5 family with nonzero 4 f electrons (R = Nd to Lu), PrMn2O5
does not show any spin driven ferroelectricity in the magnetically ordered phase. By means of high-field electric
polarization measurements up to 45 T, we have found that this exceptional candidate undergoes a spin driven
multiferroic phase under magnetic field. X-ray magnetic circular dichroism studies up to 30 T at the Pr L2 edge
show that this ferroelectricity originates from and directly couples to the ferromagnetic component of the Pr3+
spins. Experimental observations along with our generalized gradient-approximation+U calculations reveal that
this exotic ferroelectric-ferromagnetic combination stabilizes through the exchange-striction mechanism solely
driven by a 3d-4 f -type coupling, as opposed to the other RMn2O5 members with 3d-3d driven ferroelectricantiferromagnetic-
type conventional type-II multiferroicity.
Domaines
Matière Condensée [cond-mat]Origine | Fichiers produits par l'(les) auteur(s) |
---|