The influence of crystalline electrical field on magnetic and magnetocaloric properties in Er1−yTbyAl2 compounds

• Published in: Journal of magnetism and magnetic materials 2017-11, Vol.442, p.265-269
• Main Authors: Ribeiro, P.O., Alho, B.P., Alvarenga, T.S.T., Nóbrega, E.P., de Sousa, V.S.R., Carvalho, A. Magnus G., Caldas, A., Lopes, P.H.O., von Ranke, P.J.
• Format: Article
• Language: English
• Subjects: Anisotropic magnetocaloric effect; Anisotropy; Crystal structure; Crystalline electrical field; Entropy; Erbium compounds; Magnetic fields; Magnetic properties; Rare earth compounds; Rare-earth compound; Refrigeration; Terbium; Zeeman effect
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2017.06.120

•Modeling Er(1−y)TbyAl2 intermetallic compounds.•Anisotropic magnetic entropy changes in Er(1−y)TbyAl2.•Reorientation temperature in Er(1−y)TbyAl2. We report the anisotropy of magnetic field-induced entropy change in rare earth Er1-yTbyAl2 compounds (y=0.00, 0.25, 0.50, 0.75 and 1.00). In the present work, we use a model Hamiltonian that includes the crystalline electrical field anisotropy in both Er and Tb magnetic sublattices, chemical disorder in exchange interactions among Er-Er, Tb-Tb and Er-Tb magnetic ions and the Zeeman effect. We investigated the isothermal magnetic entropy change ΔST for a magnetic field of 1T rotating from a hard 〈001〉 to the easy 〈111〉 direction. We also performed a systematic analysis of the reorientation temperature as a function of the magnetic field intensity. The anisotropic magnetocaloric effect highlights the applicability of this effect on the rotating magnetic refrigeration.