Observation of minority spin character of the new electron doped   manganite La_0.7Ce_0.3MnO_3 from tunneling magnetoresistance
  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. 
C. Mitra, P. Raychaudhuri, K. Doerr, K.-H. Mueller, L. Schultz, P.M.   Oppeneer, S. Wirth