title: Origin of magnetic and magnetoelastic tweedlike precursor modulations in ferroic materials.
abstract: Based on experimental observations of modulated magnetic patterns in a Co0.5Ni0.205Ga0.295 alloy, we propose a model to describe a (purely) magnetic tweed and a magnetoelastic tweed. The former arises above the Curie (or Néel) temperature due to magnetic disorder. The latter results from compositional fluctuations coupling to strain and then to magnetism through the magnetoelastic interaction above the structural transition temperature. We discuss the origin of purely magnetic and magnetoelastic precursor modulations and their experimental thermodynamic signatures.
authors.affiliation: Department d'Estructura i Constituents de la Matèria, Universitat de Barcelona, Diagonal 647, 08028 Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Saxena
authors.forename: T
authors.initials: T
authors.lastname: Castán
authors.forename: A
authors.initials: A
authors.lastname: Planes
authors.forename: M
authors.initials: M
authors.lastname: Porta
authors.forename: Y
authors.initials: Y
authors.lastname: Kishi
authors.forename: T A
authors.initials: TA
authors.lastname: Lograsso
authors.forename: D
authors.initials: D
authors.lastname: Viehland
authors.forename: M
authors.initials: M
authors.lastname: Wuttig
authors.forename: M
authors.initials: M
authors.lastname: De Graef