Guided by the internal-reference rule and the known band offsets in III-V andII-VI diluted magnetic semiconductors, we discuss the feasibility of obtainingp-type conductivity, required for the carrier-induced ferromagnetism, as wellas the cases for which the doping by shallow impurities may lead to theferromagnetism driven by the double exchange. We consider the dependence ofkinetic exchange on the p-d hybridization, on the electronic configurations ofthe magnetic ions, and on the energies of the charge transfer between thevalence band of host materials and the magnetic ions. In the case of Mn-basedII-VI compounds, the doping by acceptors is necessary for the hole-inducedferromagnetism. The latter is, however, possible without any doping for some ofMn-, Fe- or Co-based III-V magnetic semiconductors. In nitrides with Fe or Cocarrier-induced ferromagnetism with T_C>300K is expected in the presence ofacceptor doping.
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