Magnetoresistance in electron doped Cr1-xMnxO2 double exchange ferromagnet

Electron doping in the half-metallic ferromagnet CrO2 oxide has been reached via partial Cr substitution by Mn. Synthesis of ceramic samples is accomplished under high temperature and high oxygen pressure. It is found that electron doping reduces the magnetization and the Curie temperature of the samples. Simultaneously, the low temperature and low field magnetoresistance of the samples increase. The results are discussed on the light of the current models for the electronic structure of this oxide and the possible role of segregated insulating impurity phases. (C) 2000 American Institute of Physics. [S0021-8979(00)79308-X].