Interface magnetism in Fe(2)O(3)/FeTiO(3) heterostructures

Pentcheva, Rossitza und Nabi, Hasan Sadat (2008): Interface magnetism in Fe(2)O(3)/FeTiO(3) heterostructures. In: Physical Review B, Bd. 77, Nr. 17

Abstract

To resolve the microscopic origin of magnetism in the Fe(2)O(3)/FeTiO(3)system, we have performed density functional theory calculations thattake into account on-site Coulomb repulsion. By systematically varyingthe concentration, distribution, and charge state of Ti in a hematitehost, we compile a phase diagram of the stability with respect to theend members and find a clear preference to form layered arrangements asopposed to solid solutions. The charge mismatch at the interface isaccommodated through Ti(4+) and a disproportionation in the Fe contactlayer into Fe(2+), Fe(3+), leading to uncompensated moments in thecontact layer and giving first theoretical evidence for the lamellarmagnetism hypothesis. This interface magnetism is associated withimpurity levels in the band gap, showing a half-metallic behavior andmaking Fe(2)O(3)/FeTiO(3)-heterostructures prospective materials forspintronics applications.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Geowissenschaften > Department für Geo- und Umweltwissenschaften > Kristallographie und Materialwissenschaft
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik ; 500 Naturwissenschaften und Mathematik > 540 Chemie ; 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
• Sprache: Englisch