Effect of oxygen content on the magnetic properties of multiferroic YMn(2)O(5+δ).

The effect of oxygen content on magnetic properties in the multiferroic YMn(2)O(5+δ) system was investigated with samples prepared under different oxygen pressures. Our results show that, with increasing oxygen content, the magnetic response changes from being dominated by the anomaly at ∼45 K to the one around 20 K. However, specific heat measurements and neutron powder diffraction studies indicate that the presence of the magnetic transition at ∼45 K is independent of oxygen content. The results suggest that oxygen nonstoichiometry can be one important degree of freedom in manipulating the multiferroic properties.