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Title: Critical Behavior Near the Paramagnetic-Ferromagnetic Phase Transition in La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and x = 0.5) Cobaltites

Abstract

In this work, we present the study of structural, magnetic and critical behavior of La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and 0.5) cobaltites. X-ray diffraction analysis using the Rietveld refinement shows that the sample La{sub 0.7}Sr{sub 0.3}CoO{sub 3} crystallizes in a rhombohedral distorted perovskite structure with R3̄c space group, while La{sub 0.5}Sr{sub 0.5}CoO{sub 3} exhibits both phases rhombohedric and cubic, with R3̄c and Pm3̄m space groups. Our samples exhibit thermo-magnetic irreversibility behavior in the magnetization data under a magnetic applied field of 0.05 T. The temperature dependence of magnetic susceptibility at higher temperatures for La{sub 0.7}Sr{sub 0.3}CoO{sub 3} sample reveals the presence of the Griffiths’ phase above the Curie temperature, while it follows the Curie–Weiss law perfectly for La{sub 0.5}Sr{sub 0.5}CoO{sub 3}. Different techniques including the modified Arrott plot, the Kouvel-Fisher method and the critical isotherm analysis have been used to analyze the paramagnetic-ferromagnetic phase transition. The values of the critical exponents associated to this transition were close to those expected in the mean-field model. The validity of the calculated critical exponents has been confirmed by the scaling equation of state. The determined critical exponents using various methods are found to follow the scaling equation with the magnetization datamore » scaled into two different curves below and above the critical temperature.« less

Authors:
;  [1]; ;  [2]
  1. Université de Sfax, Institut Supérieur de Biotechnologie de Sfax (Tunisia)
  2. Centre de Recherche en Numérique de Sfax, Laboratoire des Technologies des Systèmes Smart (LT2S) (Tunisia)
Publication Date:
OSTI Identifier:
22782491
Resource Type:
Journal Article
Journal Name:
Journal of Superconductivity and Novel Magnetism
Additional Journal Information:
Journal Volume: 31; Journal Issue: 2; Other Information: Copyright (c) 2018 Springer Science+Business Media, LLC, part of Springer Nature; Article Copyright (c) 2017 Springer Science+Business Media, LLC; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1557-1939
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COBALT COMPOUNDS; CRITICAL TEMPERATURE; CUBIC LATTICES; CURIE POINT; EQUATIONS OF STATE; ISOTHERMS; LANTHANUM COMPOUNDS; MAGNETIC SUSCEPTIBILITY; MAGNETIZATION; MEAN-FIELD THEORY; OXYGEN COMPOUNDS; PARAMAGNETISM; PHASE TRANSFORMATIONS; SPACE GROUPS; STRONTIUM COMPOUNDS; TEMPERATURE DEPENDENCE; TRIGONAL LATTICES; X-RAY DIFFRACTION

Citation Formats

Amor, A. Ben, Koubaa, M., E-mail: mohamedkoubaa@yahoo.fr, Cheikhrouhou-Koubaa, W., and Cheikhrouhou, A. Critical Behavior Near the Paramagnetic-Ferromagnetic Phase Transition in La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and x = 0.5) Cobaltites. United States: N. p., 2018. Web. doi:10.1007/S10948-017-4225-Z.
Amor, A. Ben, Koubaa, M., E-mail: mohamedkoubaa@yahoo.fr, Cheikhrouhou-Koubaa, W., & Cheikhrouhou, A. Critical Behavior Near the Paramagnetic-Ferromagnetic Phase Transition in La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and x = 0.5) Cobaltites. United States. doi:10.1007/S10948-017-4225-Z.
Amor, A. Ben, Koubaa, M., E-mail: mohamedkoubaa@yahoo.fr, Cheikhrouhou-Koubaa, W., and Cheikhrouhou, A. Thu . "Critical Behavior Near the Paramagnetic-Ferromagnetic Phase Transition in La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and x = 0.5) Cobaltites". United States. doi:10.1007/S10948-017-4225-Z.
@article{osti_22782491,
title = {Critical Behavior Near the Paramagnetic-Ferromagnetic Phase Transition in La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and x = 0.5) Cobaltites},
author = {Amor, A. Ben and Koubaa, M., E-mail: mohamedkoubaa@yahoo.fr and Cheikhrouhou-Koubaa, W. and Cheikhrouhou, A.},
abstractNote = {In this work, we present the study of structural, magnetic and critical behavior of La{sub 1−x}Sr{sub x}CoO{sub 3} (x = 0.3 and 0.5) cobaltites. X-ray diffraction analysis using the Rietveld refinement shows that the sample La{sub 0.7}Sr{sub 0.3}CoO{sub 3} crystallizes in a rhombohedral distorted perovskite structure with R3̄c space group, while La{sub 0.5}Sr{sub 0.5}CoO{sub 3} exhibits both phases rhombohedric and cubic, with R3̄c and Pm3̄m space groups. Our samples exhibit thermo-magnetic irreversibility behavior in the magnetization data under a magnetic applied field of 0.05 T. The temperature dependence of magnetic susceptibility at higher temperatures for La{sub 0.7}Sr{sub 0.3}CoO{sub 3} sample reveals the presence of the Griffiths’ phase above the Curie temperature, while it follows the Curie–Weiss law perfectly for La{sub 0.5}Sr{sub 0.5}CoO{sub 3}. Different techniques including the modified Arrott plot, the Kouvel-Fisher method and the critical isotherm analysis have been used to analyze the paramagnetic-ferromagnetic phase transition. The values of the critical exponents associated to this transition were close to those expected in the mean-field model. The validity of the calculated critical exponents has been confirmed by the scaling equation of state. The determined critical exponents using various methods are found to follow the scaling equation with the magnetization data scaled into two different curves below and above the critical temperature.},
doi = {10.1007/S10948-017-4225-Z},
journal = {Journal of Superconductivity and Novel Magnetism},
issn = {1557-1939},
number = 2,
volume = 31,
place = {United States},
year = {2018},
month = {2}
}