The Magnetic Properties of Hole-Doped MgO

We present a first-principles study on a new class of diluted magnetic semiconductors based on MgO with no magnetic elements. It was found that hole-doping by Mg vacancies or Li impurities leads to a spin-polarized ground state, and Curie temperatures can reach room temperature at sufficient concentrations (in the range of 15 to 30 at. %) under a homogeneously distributed condition. However, an inhomogeneous dopant distribution in MgO is the favored configuration, which indicates that spinodal decomposition leads to the room-temperature blocking temperature at smaller impurity concentrations than those estimated for room-temperature ferromagnetism under the homogeneous distribution condition.