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arXiv · 1412.3904

Upper bound for the s-d exchange integral in n-(Ga,Mn)N:Si from magnetotransport studies

R. Adhikari·W. Stefanowicz·B. Faina·M. Sawicki·T. Dietl·A. Bonanni
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Abstract

A series of recent magnetooptical studies pointed to contradicting values of the s-d exchange energy N0α in Mn-doped GaAs and GaN as well as in Fe-doped GaN. Here, a strong sensitivity of weak-localization phenomena to symmetry breaking perturbations (such as spin-splitting and spin-disorder scattering) is exploited to evaluate the magnitude of N0α for n-type wurtzite (Ga,Mn)N:Si films grown by metalorganic vapor phase epitaxy. Millikelvin magnetoresistance studies and their quantitative interpretation point to N0α < 40 meV, a value at least 5 times smaller than the one found with similar measurements on, e.g., $n$-(Zn,Mn)O. It is shown that this striking difference in the values of the s-d coupling between $n$-type III-V and II-VI dilute magnetic semiconductors can be explained by a theory that takes into account the acceptor character of Mn in III-V compounds.

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R. Adhikari, W. Stefanowicz, B. Faina, M. Sawicki, T. Dietl, A. Bonanni. 2014-12-12. Upper bound for the s-d exchange integral in n-(Ga,Mn)N:Si from magnetotransport studies. https://doi.org/10.1103/physrevb.91.205204

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