Observation of different spin behavior with temperature variation and Cr substitution in a multiferroic compound YMn2O5

In this article, the collective response of the spins is explored through low field bulk magnetic measurement for the series YMn2−xCrxO5 (x=0.0, 0.05). Low field ac susceptibility and dc magnetization of YMn2O5 shows multiple transitions in analogy to those observed in electrical measurement of the compound. Perturbing the parent compound with a small doping (2.5% Cr) causes a drastic change in the long-range magnetic behavior. It is observed that, YMn1.95Cr0.05O5 undergoes a ferrimagnetic ordering with an enhanced magnetic ordering temperature as compared to the parent, which undergoes an antiferromagnetic ordering. Appearance of spontaneous magnetization without any major change in the atomic structure is rather significant since the parent compound is an important multiferroic material. In addition, magnetic memory effect is observed in the Cr substituted compound whereas it is absent in the parent compound.

► Low field magnetic studies of YMn2O5. ► Observation of ferrimagnetic ordering in YMn1.95Cr0.05O5. ► Contrasting magnetic memory effect in the parent and doped compound.