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Ferromagnetism in Ga1-xMnxP: evidence for inter-Mn exchange mediated by localized holes within a detached impurity band

M. A. Scarpulla·B. L. Cardozo·W. M. Hlaing Oo·M. D. McCluskey·O. D. Dubon
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Abstract

We demonstrate that in ferromagnetic Ga1-xMnxP exchange is mediated by holes localized in a Mn-derived band. For x<0.06, infrared absorption and photoconductivity spectra indicate the presence of a Mn impurity band which is not merged with the valence band. At temperatures above TC (<65 K) electrical transport is dominated by excitation across this energy gap while nearest neighbor hopping dominates below TC. Magnetization measurements reveal a moment of 3.5 Bohr magnetons per substitutional Mn, while the large anomalous Hall signal unambiguously demonstrates that the ferromagnetism is carrier-mediated.

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M. A. Scarpulla, B. L. Cardozo, W. M. Hlaing Oo, M. D. McCluskey, O. D. Dubon. 2005-04-20. Ferromagnetism in Ga1-xMnxP: evidence for inter-Mn exchange mediated by localized holes within a detached impurity band. https://doi.org/10.1103/physrevlett.95.207204

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