Manipulating polar ferromagnetism in transition-metal-doped ZnO: Why manganese is different from cobalt (invited)

High-temperature magnetic ordering in Mn2+- and Co2+-doped ZnO diluted magnetic semiconductors has been predicted theoretically and confirmed experimentally to have different charge-carrier requirements. This paper summarizes some of these experimental and theoretical results and relates the different carrier polarity requirements for 300 K ferromagnetism in Mn2+:ZnO and Co2+:ZnO to differences in the charge-transfer electronic structures of these two materials. (C) 2006 American Institute of Physics.