Anomalous magnetic properties of Sr(2)YRuO(6)

Abstract

Anomalous magnetic properties of the double perovskite ruthenate compound Sr(2)YRuO(6) are reported here. Magnetization measurements as a function of temperature in low magnetic fields show clear evidence for two components of magnetic order (T(M1)similar to 32 K and T(M2)similar to 27 K) aligned opposite to each other with respect to the magnetic-field direction even though only Ru(5+) moments can order magnetically in this compound. The second component of the magnetic order at T(M2)similar to 27 K results only in a magnetization reversal, and not in the negative magnetization when the magnetization is measured in the field-cooled (FC) mode. Isothermal magnetization (M-H) measurements show hysteresis with maximum coercivity (H(c)) and remnant magnetization (M(r)) at T similar to 27 K, corroborating the presence of the two oppositely aligned magnetic moments, each with a ferromagnetic component. The two components of magnetic ordering are further confirmed by the double peak structure in the heat-capacity measurements. These anomalous properties have significance to some of the earlier results obtained for the Cu-substituted superconducting Sr(2)YRu(1-x)Cu(x)O(6) compounds.