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arXiv · 0904.2610

Ferromagnetism and Electronic Structures of Nonstoichiometric Heusler-Alloy Fe_3-xMn_xSi Epilayers Grown on Ge(111)

K. Hamaya·H. Itoh·O. Nakatsuka·K. Ueda·K. Yamamoto·M. Itakura·T. Taniyama·T. Ono·M. Miyao
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Abstract

For the study of ferromagnetic materials which are compatible with group-IV semiconductor spintronics, we demonstrate control of the ferromagnetic properties of Heusler-alloys Fe_3-xMn_xSi epitaxially grown on Ge(111) by tuning the Mn composition x. Interestingly, we obtain L2_1-ordered structures even for nonstoichiometric atomic compositions. The Curie temperature of the epilayers with x ~ 0.6 exceeds 300 K. Theoretical calculations indicate that the electronic structures of the nonstoichiometric Fe_3-xMn_xSi alloys become half-metallic for 0.75 < x < 1.5. We discuss the possibility of room-temperature ferromagnetic Fe_3-xMn_xSi/Ge epilayers with high spin polarization.

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K. Hamaya, H. Itoh, O. Nakatsuka, K. Ueda, K. Yamamoto, M. Itakura, T. Taniyama, T. Ono, M. Miyao. 2009-04-17. Ferromagnetism and Electronic Structures of Nonstoichiometric Heusler-Alloy Fe_3-xMn_xSi Epilayers Grown on Ge(111). https://doi.org/10.1103/physrevlett.102.137204

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