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arXiv · 1306.1474

Electronic excitations of magnetic impurity state in diluted magnetic semiconductor (Ga,Mn)As

M. Kobayashi·H. Niwa·Y. Takeda·A. Fujimori·Y. Senba·H. Ohashi·A. Tanaka·S. Ohya·P. N. Hai·M. Tanaka·Y. Harada·M. Oshima
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Abstract

The electronic structure of doped Mn in (Ga,Mn)As is studied by resonant inelastic X-ray scattering (RIXS). From configuration-interaction cluster-model calculations, the line shapes of the Mn $L_3$ RIXS spectra can be explained by $d$-$d$ excitations from the Mn$^{3+}$ ground state, dominated by charge-transferred states, rather than a Mn$^{2+}$ ground state. Unlike archetypical $d$-$d$ excitation, the peak widths are broader than the experimental energy resolution. We attribute the broadening to a finite lifetime of the $d$-$d$ excitations, which decay rapidly to electron-hole pairs in the host valence and conduction bands through hybridization of the Mn $3d$ orbital with the ligand band.

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M. Kobayashi, H. Niwa, Y. Takeda, A. Fujimori, Y. Senba, H. Ohashi, A. Tanaka, S. Ohya, P. N. Hai, M. Tanaka, Y. Harada, M. Oshima. 2013-06-06. Electronic excitations of magnetic impurity state in diluted magnetic semiconductor (Ga,Mn)As. https://doi.org/10.1103/physrevlett.112.107203

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