authors 
Reis, MS; Amaral, VS; Araujo, JP; Tavares, PB; Gomes, AM; Oliveira, IS 
nationality 
International 
journal 
PHYSICAL REVIEW B 
keywords 
COLOSSAL MAGNETORESISTANCE; MANGANESE OXIDES; PR0.6(CA1XSRX)(0.4)MNO3 0LESSTHANOREQUALTOXLESSTHANOREQUALTO1; MAGNETOCALORIC PROPERTIES; PEROVSKITE MANGANITES; TRANSPORTPROPERTIES; NEUTRONDIFFRACTION; PHASETRANSITION; CHARGE ORDER; PR0.7CA0.3MNO3 
abstract 
In the present work we analyze the magnetic entropy change Delta SM of the Pr1xCaxMnO3 manganites, for a wide range of Ca concentrations (0.20 <= x <= 0.95). The results for the samples with 0.20 < x <= 0.30 present the usual behavior expected for ferromagnetic systems, peaking at the Curie temperature TC. In contrast, for the chargeordered antiferromagnetic samples (0.30 < x < 0.90), an anomalous magnetic entropy change starts around the chargeordering temperature TCO, persisting for lower values of temperature. This effect is associated to a positive contribution to the magnetic entropy change due to the chargeordering Delta SCO, which is superimposed to the negative contribution from the spinordering Delta Sspin; that is described using a meanfield approximation. Supposing these contributions, we could also appraise Delta SCO(max) as a function of Ca content, which vanishes for the limits x similar to 0.30 and 0.90 and presents a deep minimum around x similar to 0.50, with two maxima at x similar to 0.35 and 0.65. We conclude that for x>0.65 only the magnetic order governs the charge ordering, contrarily to x < 0.65, where there are more than one mechanism ruling the charge ordering. Moreover, for the samples with phase coexistence (0.30 < x <= 0.40), we found extremely large values for the magnetic entropy change at low temperatures. Finally, for x>0.90, we found usual magnetic entropy change curves, peaking at the Neel temperature TN. 
publisher 
AMERICAN PHYSICAL SOC 
issn 
10980121 
year published 
2005 
volume 
71 
issue 
14 
digital object identifier (doi) 
10.1103/PhysRevB.71.144413 
web of science category 
Physics, Condensed Matter 
subject category 
Physics 
unique article identifier 
WOS:000228758700051

ciceco authors
impact metrics
journal analysis (jcr 2019):

journal impact factor 
3.575 
5 year journal impact factor 
3.511 
category normalized journal impact factor percentile 
70.187 
dimensions (citation analysis):


altmetrics (social interaction):


