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Theory of Diluted Magnetic Semiconductor Ferromagnetism

Jürgen König·Hsiu-Hau Lin·Allan H. MacDonald
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Abstract

We present a theory of carrier-induced ferromagnetism in diluted magnetic semiconductors (III_{1-x} Mn_x V) which allows for arbitrary itinerant-carrier spin polarization and dynamic correlations. Both ingredients are essential in identifying the system's elementary excitations and describing their properties. We find a branch of collective modes, in addition to the spin waves and Stoner continuum which occur in metallic ferromagnets, and predict that the low-temperature spin stiffness is independent of the strength of the exchange coupling between magnetic ions and itinerant carriers. We discuss the temperature dependence of the magnetization and the heat capacity.

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Jürgen König, Hsiu-Hau Lin, Allan H. MacDonald. 2000-05-31. Theory of Diluted Magnetic Semiconductor Ferromagnetism. https://doi.org/10.1103/physrevlett.84.5628

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