Observation of magnetization reversal and negative magnetization in Sr2YbRuO6

Detailed magnetic properties of the compound Sr(2)YbRuO(6) are presented here. The compound belongs to the family of double perovskites forming a monoclinic structure. Magnetization measurements reveal clear evidence for two components of magnetic ordering aligned opposite to each other, leading to a magnetization reversal, compensation temperature (T(*) = 34 K) and negative magnetization at low temperatures and low magnetic fields. Heat capacity measurements corroborate the presence of two components in the magnetic ordering and a noticeable third anomaly at low temperatures (∼15 K) which cannot be attributed the Schottky effect. The calculated magnetic entropy is substantially lower than that expected for the ground states of the ordered moments of Ru(5+) and Yb(3+), indicating the presence of large crystal field effects and/or incomplete magnetic ordering and/or magnetic frustrations well above the magnetic ordering. An attempt is made to explain the magnetization reversal within the frameworks of available models.