title: Ferromagnetism and electronic structures of nonstoichiometric Heusler-alloy Fe3-xMnxSi Epilayers grown on Ge(111).
abstract: For the study of ferromagnetic materials which are compatible with group-IV semiconductor spintronics, we demonstrate control of the ferromagnetic properties of Heusler-alloy Fe3-xMnxSi 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 approximately 0.6 exceeds 300 K. Theoretical calculations indicate that the electronic structures of the nonstoichiometric Fe3-xMnxSi alloys become half-metallic for 0.75 < or = x < or = 1.5. We discuss the possibility of room-temperature ferromagnetic Fe(3-x)Mn(x)Si/Ge epilayers with high spin polarization.
authors.affiliation: Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395, Japan. hamaya@ed.kyushu-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Hamaya
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: O
authors.initials: O
authors.lastname: Nakatsuka
authors.forename: K
authors.initials: K
authors.lastname: Ueda
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: M
authors.initials: M
authors.lastname: Itakura
authors.forename: T
authors.initials: T
authors.lastname: Taniyama
authors.forename: T
authors.initials: T
authors.lastname: Ono
authors.forename: M
authors.initials: M
authors.lastname: Miyao