Ca0.85Sm0.15MnO3: A mixed antiferromagnet with unusual properties | |
Article | |
关键词: RANDOM-FIELD; MAGNETIC POLARONS; PHASE-TRANSITIONS; LA0.5CA0.5MNO3; INSTABILITY; MANGANITES; SEPARATION; STATES; | |
DOI : 10.1103/PhysRevB.62.11644 | |
来源: SCIE |
【 摘 要 】
We establish a phase diagram for the electron-doped manganites Ca1-xSmxMnO3 (0 less than or equal tox less than or equal to0.15). The low-temperature insulating phase of x=0.15 is a mixed antiferromagnet with two long-range antiferromagnets, C-type (monoclinic) and G-type (orthorhombic), coexisting with short-range ferromagnetic clusters (orthorhombic). Resistivity (rho) and magnetization (M) of x= 0.15 show unusual magnetic-field history-dependent phenomena which are not observed for x less than or equal to0.12: irreversibilty between zero-field-cooled (ZFC) and field-cooled (FC) data below 120 K and hysteresis between cooling and warming for all values of magnetic fields (0 less than or equal toH less than or equal to 7T). Field cooling strongly enhances M (M-FC/M-ZFC=2.7 at H=5 T and 10 K) reduces rho (rho (FC)/rho (ZFC) = 5x10(-4) at 7 T and 10 K) and even induces metalliclike resistivity (d rho /dT>0) for H=7 T below 80 K. We discuss the possible origins of the results.
【 授权许可】
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