Irreversibility and Thermoremanent Magnetization in Y 0.8 Sr 0.2 MnO 3

Irreversible magnetization between the zero-field-cooled (ZFC) and field-cooled (FC) states in Y 1-x Sr x MnO 3(x=0 and 0.2) was investigated. YMnO 3 and Y 0.8 Sr 0.2 MnO 3 have a hexagonal structure and the lattice parameter a decreases from 7.4408 A to 7.4327 A while c increases from 12.2244 A to 12.2287 A for YMnO 3 and Y 0.8 Sr 0.2 MnO 3 , respectively. An anomaly is observed at around 74 K in ZFC and FC magnetization measurements for YMnO 3 , whereas in Y 0.8 Sr 0.2 MnO 3 the σ ZFC and σ FC are split at low temperature, indicating glass-like behavior.