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arXiv · 1209.4790

Dominant itinerant ferromagnetism in Eu0.5Sr0.5CoO3: evidences from both critical analysis and Rhodes-Wohlfarth's criterion

Renwen Li·Feng Li·Jun Fang·Wei Tong·Changjin Zhang·Li Pi·Yuheng Zhang
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Abstract

The critical behaviors of ferromagnet Eu0.5Sr0.5CoO3 arround TC=140.5K have been comprehensively investigated by analyzing a series of isothermal magnetization M(H) curves. Both Modified Arrott plot and Kouvel-Fisher methods give nearly the same critical exponents, which scale nicely the M(H) curves into two different branches below and above TC. The exponents {\gamma}=1.044 and {\delta}=3.06 demonstrate the relevance of mean-field characters for this material. The conclusion of mean-field behavior proves a dominant itinerant ferromagnetism (FM) due to a long range exchange interaction in the system. Meanwhile, by using Rhodes-Wohlfarth's criterion [P. Rhodes and E. P. Wohlfarth, Proc. R. Soc. Lond. A 273, 247 (1963)], it is further confirmed that the itinerant FM dominates in the system.

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Renwen Li, Feng Li, Jun Fang, Wei Tong, Changjin Zhang, Li Pi, Yuheng Zhang. 2012-09-21. Dominant itinerant ferromagnetism in Eu0.5Sr0.5CoO3: evidences from both critical analysis and Rhodes-Wohlfarth's criterion. https://doi.org/10.1016/j.jallcom.2013.06.028

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