Comparison of the irreversible thermomagnetic behaviour of some ferro- and ferrimagnetic systems

Bulletin of materials science

P A Joy²  S K Date²  P S Anil Kumar¹ 

[1] Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India$$Information Storage Technology Group, MESA Research Institute, University of Twente, 7500 AE Enschede, The Netherlands$$Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, IndiaPhysical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India$$Information Storage Technology Group, MESA Research Institute, University of Twente, 7500 AE Enschede, The Netherlands$$Information Storage Technology Group, MESA Research Institute, University of Twente, 7500 AE Enschede, The NetherlandsPhysical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India$$Information Storage Technology Group, MESA Research Institute, University of Twente, 7500 AE Enschede, The Netherlands$$;Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India$$Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, IndiaPhysical and Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India$$

关键词: Ferromagnet;    ferrimagnet;    thermomagnetic irreversibility;    magnetocrystalline anisotropy;    coercivity.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

The magnetic behaviour of two ferromagnetic oxides and two ferrimagnetic oxides (ferrites) are compared to study the effect of magnetocrystalline anisotropy on thermal-history-dependence of magnetization of these ordered magnetic systems. All four compounds show thermomagnetic irreversibility (𝑀_FC > 𝑀_ZFC) below a certain temperature, ð‘�??_irr. The highly anisotropic ferromagnetic oxide, SrRuO₃ and the hard ferrite, SrFe₁₂O₁₉ show sharp peaks below ð‘�??_ð‘�? in their 𝑀_ZFC(ð‘�??) curves, whereas for the soft ferrite Ni_0.8Zn_0.2Fe₂O₄ and the low anisotropic ferromagnetic oxide La_0.7Ca_0.3MnO₃ only a broad maximum is observed in 𝑀_ZFC, when measured in small magnetic fields. The shapes of the 𝑀_ZFC(ð‘�??) curves are inversely-related to the magnitude of the coercivities (𝐻_c) of the compounds in relation to the applied field, and the temperature dependence of (𝐻_c). 𝑀_FCand 𝑀_ZFC are related through the coercivity for all four magnetic systems.

【 授权许可】

Unknown