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High Curie temperatures in (Ga,Mn)N from Mn clustering

Teemu Hynninen·Hannes Raebiger·Andres Ayuela·J. von Boehm
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Abstract

The effect of microscopic Mn cluster distribution on the Curie temperature (Tc) is studied using density-functional calculations. We find that the calculated Tc depends crucially on the microscopic cluster distribution, which can explain the abnormally large variations in experimental Tc values from a few K to well above room temperature. The partially dimerized Mn_2-Mn_1 distribution is found to give the highest Tc > 500 K, and in general, the presence of the Mn_2 dimer has a tendency to enhance Tc. The lowest Tc values close to zero are obtained for the Mn_4-Mn_1 and Mn_4-Mn_3 distributions.

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Teemu Hynninen, Hannes Raebiger, Andres Ayuela, J. von Boehm. 2006-02-28. High Curie temperatures in (Ga,Mn)N from Mn clustering. https://doi.org/10.1063/1.2188036

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