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arXiv · 0708.3296

Observation of strong-coupling effects in a diluted magnetic semiconductor (Ga,Fe)N

W. Pacuski·P. Kossacki·D. Ferrand·A. Golnik·J. Cibert·M. Wegscheider·A. Navarro-Quezada·A. Bonanni·M. Kiecana·M. Sawicki·T. Dietl
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Abstract

A direct observation of the giant Zeeman splitting of the free excitons in (Ga,Fe)N is reported. The magnetooptical and magnetization data imply the ferromagnetic sign and a reduced magnitude of the effective p-d exchange energy governing the interaction between Fe^{3+} ions and holes in GaN, N_0 beta^(app) = +0.5 +/- 0.2 eV. This finding corroborates the recent suggestion that the strong p-d hybridization specific to nitrides and oxides leads to significant renormalization of the valence band exchange splitting.

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W. Pacuski, P. Kossacki, D. Ferrand, A. Golnik, J. Cibert, M. Wegscheider, A. Navarro-Quezada, A. Bonanni, M. Kiecana, M. Sawicki, T. Dietl. 2007-08-24. Observation of strong-coupling effects in a diluted magnetic semiconductor (Ga,Fe)N. https://doi.org/10.1103/physrevlett.100.037204

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