Magnetic and Magnetocaloric Properties of Multiferroic Oxides Gd0.5Y0.5MnO3 and Eu0.5Dy0.5MnO3

• Published in: IEEE transactions on magnetics 2021-02, Vol.57 (2), p.1-5
• Main Authors: Behera, P. Suchismita, Nirmala, R.
• Format: Article
• Language: English
• Subjects: Anomalies; Antiferromagnetism; Crystal structure; Electric resistance; Electrical resistivity; Ferromagnetic materials; Gadolinium; Low temperature; Magnetic properties; Magnetic transitions; Magnetism; Magnetization; magnetocaloric effect; Manganese; Rare earth elements; Rare earth metals; rare-earth manganites; Specific heat; Temperature dependence; Yttrium compounds
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2020.3020422

In this article, crystal structure, magnetism, heat capacity, magnetocaloric effect (MCE), and electrical resistivity of mixed rare-earth Gd 0.5 Y 0.5 MnO 3 and Eu 0.5 Dy 0.5 MnO 3 manganites have been studied. Temperature-dependent magnetization M(T) measurements suggest an antiferromagnetic order just below 6 K in Gd 0.5 Y 0.5 MnO 3 , while no magnetic transition has been observed down to 5 K in Eu 0.5 Dy 0.5 MnO 3 . Heat capacity data reveal anomalies at 40 and 42 K in Gd 0.5 Y 0.5 MnO 3 and Eu 0.5 Dy 0.5 MnO 3 , and these may correspond to Mn magnetic order as previously reported. The magnetization values are 2.8 and 3 μ B /f.u. in 70 kOe field at 5 K for Gd 0.5 Y 0.5 MnO 3 and Eu 0.5 Dy 0.5 MnO 3 , respectively. MCE has been estimated in terms of isothermal magnetic entropy change (ΔS m ) at low temperatures. The maximum values of ΔS m are about -11 and -6.2 J kg -1 , respectively, for Gd 0.5 Y 0.5 MnO 3 and Eu 0.5 Dy 0.5 MnO 3 samples for a field change of 70 kOe at 8 K. Electrical resistivity of Gd 0.5 Y 0.5 MnO 3 and Eu 0.5 Dy 0.5 MnO 3 shows variable range polaron hopping behavior in the temperature range of 210-350 K.