Predicted model of magnetocaloric effect in BiFeO3-based multiferroics

• Published in: Solid state sciences 2019-09, Vol.95, p.105920, Article 105920
• Main Authors: Makoed, I.I., Amirov, A.A., Liedienov, N.A., Pashchenko, A.V., Yanushkevich, K.I.
• Format: Article
• Language: English
• Subjects: Magnetic phase transition; Magnetocaloric effect; Multiferroics; Néel temperature; Rare-earth ion; Relative cooling power
• ISSN: 1293-2558; 1873-3085
• DOI: 10.1016/j.solidstatesciences.2019.06.009

Structure, magnetic properties and magnetocaloric effect in synthesized Bi-based multiferroics with a partial isovalent substitution of bismuth (III) cations for rare-earth elements (R = La, Nd, Sm, Eu, Gd, Dy, Er) have been studied. The samples have been prepared by the solid-state reaction method under cold pressing at high pressure (4 GPa). Proposed, for the first time, has been a modified phenomenological model for describing temperature dependences of magnetization and investigating a magnetocaloric effect within “weak ferromagnetic-antiferromagnetic” and “antiferromagnetic-paramagnetic” magnetic phase transition regions. Systematic changes of thermodynamic characteristics have been found out to depend on the degree of replacement and the type of a substituted cation. [Display omitted] •Magnetic properties and thermodynamic parameters have been studied in RxBi1-xFeO3•Semi-empirical model for describing M(T) dependencies in multiferroics was modified•A modified model for prediction of MCE in multiferroics was used for the first time•Heat capacity, entropy, relative cooling power values were calculated for RxBi1-xFeO3•The maximal values of thermodynamic parameters are observed for RBFO with R = Nd, Gd