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Self-compensation in manganese-doped ferromagnetic semiconductors

Steven C. Erwin·A. G. Petukhov
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Abstract

We present a theory of interstitial Mn in Mn-doped ferromagnetic semiconductors. Using density-functional theory, we show that under the non-equilibrium conditions of growth, interstitial Mn is easily formed near the surface by a simple low-energy adsorption pathway. In GaAs, isolated interstitial Mn is an electron donor, each compensating two substitutional Mn acceptors. Within an impurity-band model, partial compensation promotes ferromagnetic order below the metal-insulator transition, with the highest Curie temperature occurring for 0.5 holes per substitutional Mn.

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Steven C. Erwin, A. G. Petukhov. 2002-09-13. Self-compensation in manganese-doped ferromagnetic semiconductors. https://doi.org/10.1103/physrevlett.89.227201

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