CEMS study of the growth and properties of Fe3O4 films

Epitaxial growth of γ-Ga2O3 films by mist chemical vapor deposition

“…The orientations of b-phase domains were (100) and (À 201) on spinel and sapphire substrates, respectively, which are coincide with those of previously reported growth on cubic (100) MgO and (0001) sapphire substrates, respectively [30,31]. It is worth mentioning that such flexible phase transition of Ga 2 O 3 polymorphs that we found is very similar to that observed for Fe 3 O 4 /Fe 2 O 3 films grown on (100) MgO and (0001) sapphire substrates by using MBE [32,33].…”

Structure, charge distribution, and electron hopping dynamics in magnetite (Fe3O4) (100) surfaces from first principles

“…In principle, at environmentally relevant conditions, the degree of reductive adsorption that occurs on a given magnetite surface varies directly as a function of Fe 2+ availability, which ultimately depends upon both the arrangement of atoms at the surface and the rate at which electrons can migrate through the structure to surface sites. The structure of magnetite (1 0 0) has been reasonably well studied to date, with a ( p 2 Â p 2)R45°reconstruction observed most commonly following annealing under vacuum conditions (Fujii et al, 1990(Fujii et al, , 1994Shvets et al, 1992Shvets et al, , 2004Wiesendanger et al, 1992a,b;Coey et al, 1993;Tarrach et al, 1993;Voogt et al, 1995;Gaines et al, 1997;Kim et al, 1997;Chambers and Joyce, 1999;Peden et al, 1999;Seoighe et al, 1999;Stanka et al, 2000;Mijiritskii and Boerma, 2001;Mariotto et al, 2002;Ceballos et al, 2004;Spiridis et al, 2004;Fonin et al, 2005;Jordan et al, 2005Jordan et al, , 2006aPentcheva et al, 2005Pentcheva et al, , 2008Subagyo et al, 2005;Wang et al, 2006;Stoltz et al, 2008). This reconstruction can be achieved by removing half a layer of Fe tet (A-type), or by introducing oxygen defects in an Fe oct -terminated layer (B-type); the latter can also be stabilized without oxygen defects by inducing a distortion (i.e., Jahn-Teller wave) to the surface Fe oct chains Fonin et al, 2005;Pentcheva et al, 2005Pentcheva et al, , 2008.…”

Enhancement of the magnetization saturation in magnetite (100) epitaxial films by thermo-chemical treatment

“…It was reported that antiphase boundaries ͑APBs͒ exist in epitaxial magnetite films. [1][2][3] In the case of the growth of magnetite on the most common substrate, MgO, the APBs arise from the fact that the lattice constant of magnetite is twice that of the substrate resulting in half-lattice period shifts between some of the nucleation islands. Antiferromagnetic exchange through the APBs makes saturating this soft magnetic material difficult.…”