Influence of higher sodium substitutions on magnetic entropy change and transition temperature in lanthanum manganites

Bulletin of materials science

M R Anantharaman¹  N Sethulakshmi¹  I A Al Omari² 

[1] Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala, India$$Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala, IndiaDepartment of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala, India$$;Department of Physics, Sultan Qaboos University, PC 123 Muscat, Sultanate of Oman$$Department of Physics, Sultan Qaboos University, PC 123 Muscat, Sultanate of OmanDepartment of Physics, Sultan Qaboos University, PC 123 Muscat, Sultanate of Oman$$

关键词: Magnetic materials;    manganites;    magnetic entropy change.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Present investigation focuses on the variation of magnetic entropy change for higher sodium substitution above 50% in lanthanum manganites. Magnetic measurements indicated that all samples exhibit a ferromagnetic ordering near room temperature. Magnetic isotherms for different temperatures above and below 300 K were recorded and the magnetic entropy change for compositions belonging to La_{1−ð�?��?}Na_ð‘�? MnO₃ for ð‘�? = 0.6 to 0.9 in steps of 0.1 was estimated for different applied magnetic fields. It has been found that the compositions having a Na substitution of 0.6 are having the largest entropy change, and the entropy change increases with applied magnetic field for all compositions. The change in entropy also decreases with increase in substitution of sodium. A notable change in transition temperature with Na concentration is also found in this sample series.

【 授权许可】

Unknown