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Observation of minority spin character of the new electron doped manganite La_0.7Ce_0.3MnO_3 from tunneling magnetoresistance

C. Mitra·P. Raychaudhuri·K. Doerr·K. -H. Mueller·L. Schultz·P. M. Oppeneer·S. Wirth
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Abstract

We report the magnetotransport characteristics of a trilayer ferromagnetic tunnel junction build of an electron doped manganite (La_0.7Ce_0.3MnO_3) and a hole doped manganite (La_0.7Ca_0.3MnO_3). At low temperatures the junction exhibits a large positive tunneling magnetoresistance (TMR), irrespective of the bias voltage. At intermediate temperatures below T_C the sign of the TMR is dependent on the bias voltage across the junction. The magnetoresistive characteristics of the junction strongly suggest that La_0.7Ce_0.3MnO_3 is a minority spin carrier ferromagnet with a high degree of spin polarization, i.e. a transport half metal.

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C. Mitra, P. Raychaudhuri, K. Doerr, K. -H. Mueller, L. Schultz, P. M. Oppeneer, S. Wirth. 2002-10-11. Observation of minority spin character of the new electron doped manganite La_0.7Ce_0.3MnO_3 from tunneling magnetoresistance. https://doi.org/10.1103/physrevlett.90.017202

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