Controlling the half-metallicity of Heusler/Si(1 1 1) interfaces by a monolayer of Si–Co–Si. (9th August 2016)

• Record Type: Journal Article
• Authors: Nedelkoski, Zlatko; Kepaptsoglou, Demie; Ghasemi, Arsham; Kuerbanjiang, Balati; Hasnip, Philip J; Yamada, Shinya; Hamaya, Kohei; Ramasse, Quentin M; Hirohata, Atsufumi; Lazarov, Vlado K
• Is Part Of: Journal of physics. Volume 28:Number 39(2016)
• Publication Date: 2016-08-09
• Subjects: half-metals -- spintronics -- Heusler alloys -- spin-injection; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/28/39/395003
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: By using first-principles calculations we show that the spin-polarization reverses its sign at atomically abrupt interfaces between the half-metallic Co2 (Fe, Mn)(Al, Si) and Si(1 1 1). This unfavourable spin-electronic configuration at the Fermi-level can be completely removed by introducing a Si–Co–Si monolayer at the interface. In addition, this interfacial monolayer shifts the Fermi-level from the valence band edge close to the conduction band edge of Si. We show that such a layer is energetically favourable to exist at the interface. This was further confirmed by direct observations of CoSi2 nano-islands at the interface, by employing atomic resolution scanning transmission electron microscopy.