4f spin driven ferroelectric-ferromagnetic multiferroicity in PrMn2O5 under a magnetic field

International audienceIn contrast to all other members of the RMn2O5 family with nonzero 4 f electrons (R = Nd to Lu), PrMn2O5does not show any spin driven ferroelectricity in the magnetically ordered phase. By means of high-field electricpolarization measurements up to 45 T, we have found that this exceptional candidate undergoes a spin drivenmultiferroic phase under magnetic field. X-ray magnetic circular dichroism studies up to 30 T at the Pr L2 edgeshow 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 thatthis exotic ferroelectric-ferromagnetic combination stabilizes through the exchange-striction mechanism solelydriven by a 3d-4 f -type coupling, as opposed to the other RMn2O5 members with 3d-3d driven ferroelectricantiferromagnetic-type conventional type-II multiferroicity