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arXiv · 0711.3257

Depth profile photoemission study of thermally diffused Mn/GaAs (001) interfaces

Y. Osafune·G. S. Song·J. I. Hwang·Y. Ishida·M. Kobayashi·K. Ebata·Y. Ooki·A. Fujimori·J. Okabayashi·K. Kanai·K. Kubo·M. Oshima
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Abstract

We have performed a depth profile study of thermally diffused Mn/GaAs (001) interfaces using photoemission spectroscopy combined with Ar$^+$-ion sputtering. We found that Mn ion was thermally diffused into the deep region of the GaAs substrate and completely reacted with GaAs. In the deep region, the Mn 2$p$ core-level and Mn 3$d$ valence-band spectra of the Mn/GaAs (001) sample heated to 600 $^{\circ}$C were similar to those of Ga$_{1-x}$Mn$_x$As, zinc-blende-type MnAs dots, and/or interstitial Mn in tetrahedrally coordinated by As atoms, suggesting that the Mn 3$d$ states were essentially localized but were hybridized with the electronic states of the host GaAs. Ferromagnetism was observed in the dilute Mn phase.

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Y. Osafune, G. S. Song, J. I. Hwang, Y. Ishida, M. Kobayashi, K. Ebata, Y. Ooki, A. Fujimori, J. Okabayashi, K. Kanai, K. Kubo, M. Oshima. 2008-06-08. Depth profile photoemission study of thermally diffused Mn/GaAs (001) interfaces. https://doi.org/10.1063/1.2931040

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