Asymmetry of electron and hole doping in YMnO3 - art. no. 125127

We synthesized hexagonal YMnO3 doped with tetravalent Zr ions and studied t he electronic and magnetic properties. Zr substitution creates a mixed Mn3-Mn2+ system, instead of the conventional Mn3+-Mn4+ of colossal magnetoresi stance manganites. The YMnO3 system displays a pronounced asymmetry for ele ctron and hole doping. Hole doping results in a conducting state, whereas e lectron doping retains the insulating state. This asymmetry is a consequenc e of the crystal field splitting of the Mn ions in trigonal bipyramidal coo rdination.