Cluster-glass state and the effect of A-site magnetism in electron-doped manganites

The magnetic properties of Y 0.35Ln0.05Ca0.6MnO3 (Ln = La, Pr, Nd, Sm, Gd, Dy) have been investigated thoroughly. The small average cationic radius 〈rA〉 of the present system results in a short-range antiferromagnetic charge-ordering (AFM-CO) state in the manganites. With the decrease of temperature, a super-exchange interaction begins to establish itself between the remaining disordered Mn ions after the formation of the short-range CO state. Then, the reentrant cluster-glass state originates from the frustration between the FM order in the clusters and the AFM interactions present in the background matrix. However, the large magnetic moments of Gd3+ and Dy3+ ions apply an internal magnetic field on the Mn3+ and Mn4+ ions, which results in the suppression of the cluster-glass state.