title: Magnetization process in Er2Ti2O7 at very low temperature.
abstract: We present a model which accounts for the high-field magnetization at very low temperature in the frustrated pyrochlore compound Er2Ti2O7. In Er2Ti2O7, the Er(3+) ion has a planar crystal field anisotropy and the material undergoes a transition to antiferromagnetism at TN = 1.2 K. Our model is a mean-field self-consistent calculation involving the four rare earth sites of a tetrahedron, the building unit of the pyrochlore lattice. It includes the full crystal field Hamiltonian, the infinite range dipolar interaction and anisotropic nearest neighbour exchange described by a 4-component tensor. We discuss the equivalence of our treatment of the exchange tensor, taken to be diagonal in a frame linked to a rare earth-rare earth bond, with the pseudo-spin Hamiltonian recently developed for Kramers doublets in a pyrochlore lattice.
authors.affiliation: CEA, Centre de Saclay, IRAMIS/Service de Physique de l'Etat Condensé, F-91191 Gif-sur-Yvette, France. pierre.bonville@cea.fr
authors.forename: P
authors.initials: P
authors.lastname: Bonville
authors.forename: S
authors.initials: S
authors.lastname: Petit
authors.forename: I
authors.initials: I
authors.lastname: Mirebeau
authors.forename: J
authors.initials: J
authors.lastname: Robert
authors.forename: E
authors.initials: E
authors.lastname: Lhotel
authors.forename: C
authors.initials: C
authors.lastname: Paulsen
mesh_terms: D016880:Anisotropy; D003080:Cold Temperature; D004578:Electron Spin Resonance Spectroscopy; D004871:Erbium / Q000737:chemistry*; D008280:Magnetics; D008958:Models, Molecular; D010087:Oxides / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D010087:Oxides; C093389:erbium oxide; C009495:titanium dioxide; D004871:Erbium; D014025:Titanium