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Excitonic giant Zeeman effect in GaN:Mn^3+

W. Pacuski·D. Ferrand·J. Cibert·J. A. Gaj·A. Golnik·P. Kossacki·S. Marcet·E. Sarigiannidou·H. Mariette
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Abstract

We describe a direct observation of the excitonic giant Zeeman splitting in (Ga,Mn)N, a wide-gap III-V diluted magnetic semiconductor. Reflectivity and absorption spectra measured at low temperatures display the A and B excitons, with a shift under magnetic field due to s,p-d exchange interactions. Using an excitonic model, we determine the difference of exchange integrals between Mn^3+ and free carriers in GaN, N_0(alpha-beta)=-1.2 +/- 0.2 eV. Assuming a reasonable value of alpha, this implies a positive sign of beta which corresponds to a rarely observed ferromagnetic interaction between the magnetic ions and the holes.

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W. Pacuski, D. Ferrand, J. Cibert, J. A. Gaj, A. Golnik, P. Kossacki, S. Marcet, E. Sarigiannidou, H. Mariette. 2007-03-02. Excitonic giant Zeeman effect in GaN:Mn^3+. https://doi.org/10.1103/physrevb.76.165304

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