Ferromagnetism of magnetic semiconductors—Zhang-Rice limit
نویسندگان
چکیده
It is suggested that p-d hybridization contributes significantly to the hole binding energy Eb of Mn acceptors in III-V compounds, leading in an extreme case to the formation of Zhang-Rice-like small magnetic polarons. The model explains both strong increase of Eb and evolution of Mn spinresonance spectrum with the magnitude of valence-band offsets. For such a structure of Mn impurity in III-V materials, possible models accounting for the recently determined Curie temperature of about 940 K in a compensated Ga0.91Mn0.09N are discussed.
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