Modification of the order of the magnetic phase transition in cobaltites without changing their crystal space group
File(s)
Accepted version
Author(s)
Law, jiayan
Franco, Victorino
Conde, A
Skinner, Stephen
Pramana, Stevin
Type
Journal Article
Abstract
It has been found that GdBa1-xSrxCo2O6-δ can exhibit consecutive magnetic transitions: antiferromagnetic-ferromagnetic (AFM-FM) transition followed by ferromagnetic-paramagnetic transition (FM-PM), which give rise to a coexistence of inverse and conventional magnetocaloric effect (MCE), respectively. In the pristine compound (x = 0), its AFM-FM transition is shown to belong to a first-order phase transition and the FM-PM to a second-order type. Despite it is widely known that the properties of cobaltites are highly influenced by their oxygen content and type of doping carriers, in this work, further evaluation using magnetocaloric analysis (universal curve method and a quantitative criterion using magnetic field dependence of the magnetic entropy change) reveals that the first-order AFM-FM phase transition converts into a second-order character with just Sr doping of x = 0.1 (despite of having the same space group at room temperature and type of dopant carrier as x = 0), severely affecting its thermomagnetic properties. Moreover, the peaks of these two MCE span over a temperature range that is larger than those reported for cobaltite-type materials, making it closer to room temperature applications.
Date Issued
2019-03-10
Date Acceptance
2018-11-02
Citation
Journal of Alloys and Compounds, 2019, 777, pp.1080-1086
ISSN
0925-8388
Publisher
Elsevier
Start Page
1080
End Page
1086
Journal / Book Title
Journal of Alloys and Compounds
Volume
777
Copyright Statement
© 2018 Elsevier B.V. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/M014142/1
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Physical
Materials Science, Multidisciplinary
Metallurgy & Metallurgical Engineering
Chemistry
Materials Science
Perovskite cobaltites
Thermomagnetic phase transitions
SPIN-STATE
PEROVSKITE COBALTITE
MAGNETORESISTANCE
TRANSPORT
GD
0912 Materials Engineering
0914 Resources Engineering And Extractive Metallurgy
0204 Condensed Matter Physics
Materials
Publication Status
Published
Date Publish Online
2018-11-12