Structures and electromagnetic properties of the A-site ordered/disordered manganites; RBaMn2O6/R0.5Ba0.5MnO3 (R = Y and rare earth elements)

Abstract

The discovery of novel structural and physical properties in the $A$-site ordered manganite $R$BaMn$_2$O$_6$ ($R$ = Y and rare earth elements) has demanded new comprehension about perovskite manganese oxides. In the present study, the $A$-site disordered form $R$$_{0.5}$Ba$_{0.5}$MnO$_3$ was successfully synthesized and compared with $R$BaMn$_2$O$_6$ in the structures and electromagnetic properties. $R$$_{0.5}$Ba$_{0.5}$MnO$_3$ has a primitive cubic perovskite cell. Unexpectedly the magnetic glassy states are dominant as the ground state for $R$$_{0.5}$Ba$_{0.5}$MnO$_3$. A peculiar behavior, the steplike ultrasharp magnetization and resistivity change, has been observed in Pr$_{0.5}$Ba$_{0.5}$MnO$_3$.