Determining the first-order character of La(Fe,Mn,Si)(13)

File Description SizeFormat 
Criticality paper vs10.pdfAccepted version1.23 MBAdobe PDFView/Open
Title: Determining the first-order character of La(Fe,Mn,Si)(13)
Authors: Bratko, M
Lovell, E
Caplin, AD
Basso, V
Barcza, A
Katter, M
Cohen, LF
Item Type: Journal Article
Abstract: Definitive determination of first-order character of the magnetocaloric magnetic transition remains elusive. Here we use a microcalorimetry technique in two modes of operation to determine the contributions to entropy change from latent heat and heat capacity separately in an engineered set of La ( Fe , Mn , Si ) 13 samples. We compare the properties extracted by this method with those determined using magnetometry and propose a model-independent parameter that would allow the degree of first-order character to be defined across different families of materials. The microcalorimetry method is sufficiently sensitive to allow observation at temperatures just above the main magnetic transition of an additional peak feature in the low field heat capacity associated with the presence of Mn in these samples. The feature is of magnetic origin but is insensitive to magnetic field, explicable in terms of inhomogeneous occupancy of Mn within the lattice resulting in antiferromagnetic ordered Mn clusters.
Issue Date: 13-Feb-2017
Date of Acceptance: 16-Jan-2017
URI: http://hdl.handle.net/10044/1/45551
DOI: https://dx.doi.org/10.1103/PhysRevB.95.064411
ISSN: 2469-9950
Publisher: American Physical Society
Journal / Book Title: PHYSICAL REVIEW B
Volume: 95
Issue: 6
Copyright Statement: © 2017 American Physical Society. Phys. Rev. B 95, 064411 – Published 13 February 2017.
Sponsor/Funder: Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Imperial College Trust
Commission of the European Communities
Engineering & Physical Science Research Council (EPSRC)
Funder's Grant Number: EP/E016243/1
EP/G060940/1
PHES_P43111
310748
DOCTORAL PRIZE
Keywords: Science & Technology
Physical Sciences
Physics, Condensed Matter
Physics
ELECTRON METAMAGNETIC LA(FE0.88SI0.12)(13)H-Y
MAGNETIC ENTROPY CHANGE
MAGNETOCALORIC PROPERTIES
SPIN FLUCTUATIONS
MN
TEMPERATURE
TRANSITIONS
MAGNETOSTRICTION
FERROMAGNETISM
COMPOUND
Publication Status: Published
Article Number: ARTN 064411
Appears in Collections:Physics
Experimental Solid State
Faculty of Natural Sciences



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commonsx