Thermodynamic model of the magnetocaloric effect near the first-order magnetic phase transitions

Re-entrant magnetic phase transitions in Ce(Fe1–xMx)2 systems (where M=Al, Ru, Co, etc.) are being investigated by various research groups. It has been observed that the system goes from a paramagnetic to ferromagnetic state followed by an almost complete loss of magnetization as the temperature is lowered. We have done systematic experimental measurements of magnetization, ac susceptibility, electrical resistivity, and thermal expansion on the Ce(Fe1–xCox)2 system. It is found that as the temperature is decreased, the system goes from para- to ferro- to antiferro-magnetic phase. The ferro- to antiferro-magnetic phase transition is a first order transition. Our experimental results are consistent with the magnetic phase diagram predictions by Moriya and Usami's theory of strongly interacting itinerant electron systems.

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Soft surface magnons and the first-order magnetic phase transitions in antiferromagnetic hematite

Physical Review B ◽

10.1103/physrevb.10.243 ◽

1974 ◽

Vol 10 (1) ◽

pp. 243-254 ◽

Cited By ~ 26

Author(s):

H. Chow ◽

F. Keffer

Keyword(s):

Phase Transitions ◽

Magnetic Phase ◽

Magnetic Phase Transitions ◽

First Order ◽

Soft Surface

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Three first order magnetic phase transitions in re-entrant ferromagnet PrMn1.4Fe0.6Ge2

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2010.06.096 ◽

2010 ◽

Vol 505 (2) ◽

pp. L38-L42 ◽

Cited By ~ 6

Author(s):

R. Zeng ◽

J.L. Wang ◽

L. Lu ◽

W.X. Li ◽

S.J. Campbell ◽

...

Keyword(s):

Phase Transitions ◽

Magnetic Phase ◽

Magnetic Phase Transitions ◽

First Order

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Change in the Resistivity of bcc and bct FeRh Alloys at First-Order Magnetic Phase Transitions

Journal of the Physical Society of Japan ◽

10.1143/jpsj.64.3978 ◽

1995 ◽

Vol 64 (10) ◽

pp. 3978-3985 ◽

Cited By ~ 18

Author(s):

Shinji Yuasa ◽

Takashi Akiyama ◽

Hideki Miyajima ◽

Yoshichika Otani

Keyword(s):

Phase Transitions ◽

Magnetic Phase ◽

Magnetic Phase Transitions ◽

First Order

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First-order magnetic phase transitions in thin films

JETP Letters ◽

10.1134/s0021364006020081 ◽

2006 ◽

Vol 83 (2) ◽

pp. 79-82

Author(s):

J. -P. Ader ◽

A. I. Buzdin

Keyword(s):

Thin Films ◽

Phase Transitions ◽

Magnetic Phase ◽

Magnetic Phase Transitions ◽

First Order

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The Magnetic Phase Transitions and Magnetocaloric Effect in the Ho(Co1-XAlx)2 and Tb(Co1-XAlx)2 Compounds

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.168-169.119 ◽

2010 ◽

Vol 168-169 ◽

pp. 119-121 ◽

Cited By ~ 1

Author(s):

S.A. Nikitin ◽

G.A. Tskhadadze ◽

I.A. Ovchenkova ◽

D.A. Zhukova ◽

T.I. Ivanova

Keyword(s):

Phase Transitions ◽

Curie Temperature ◽

Magnetocaloric Effect ◽

Magnetic Phase ◽

Magnetic Ordering ◽

Magnetic Phase Transitions ◽

Al Content ◽

Direct Measurements ◽

Magnetic Ordering Temperature ◽

Ferrimagnetic Structure

Direct measurements of the magnetocaloric effect (MCE) and magnetization have been conducted for the R(Co1-xAlx)2 (R = Tb, Ho) compounds. It was found that the small substitutions of Co by nonmagnetic Al lead to an increase both of the magnetic ordering temperature and the value of MCE. The following increase in Al content decreases the Curie temperature and the value of MCE. The analyses of the MCE effect is conducted considering the ferrimagnetic structure and the itinerant nature of these compounds.

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