Anomalous field dependence of the inverse magnetocaloric effect in Ce(Fe0.93Ru0.07)2

A summary of detailed isothermal magnetization along with the ac susceptibility measurements on Ce(Fe0.93Ru0.07)2 is presented. Near the first-order transition, i.e. near 110 K, Ce(Fe0.93Ru0.07)2 displays a large positive magnetic entropy change, ΔSm, of 7.8 J/kg K in fields of only 2 T, i.e. it displays a strong inverse magnetocaloric (MCE) effect, as expected, on entering an antiferromagnetic (AF) state. However, the variation of the magnitude and width of this entropy change with field are anomalous when compared with model predictions, the former increasing with applied field below 2 T, while the latter exceeds 60 K in a field of 8 T.