Magnetic entropy changes of SmMn2Ge2 under high pressure

Keiichi Koyama; Shihou Miura; Hironari Okada; Toru Shigeoka; Kazuo Watanabe

doi:10.2320/matertrans.48.451

Magnetic entropy changes of SmMn₂Ge₂ under high pressure

Keiichi Koyama, Shihou Miura, Hironari Okada, Toru Shigeoka, Kazuo Watanabe

Research output: Contribution to journal › Article › peer-review

2 Citations (Scopus)

Abstract

In order to obtain the information about magnetic states of reentrant ferromagnet, SmMn₂Ge₂, we have studied the pressure effect on magnetocaloric properties by magnetization measurements under high pressures up to 1.2 GPa in the temperature range from 5 to 300 K. Using the Maxwell relation, we estimated the magnetic entropy change |ΔS_M| to be 0.65 JK^-1mol^-1 at T₁ (= 100K) and 0.53 JK ^-1mol^-1 at T₂ (= 150K) under 0.1 MPa. By applying pressures up to 0.5 GPa, |ΔS_M(T₁)| is enhanced (2.0 JK^-1 mol^-1), while |ΔS _M(T₂)| is slightly suppressed (0.4 JK^-1 mol^-1). The obtained values of |ΔS_M| were discussed on the basis of a mean field theory using a two-sublattice model.

Original language	English
Pages (from-to)	451-454
Number of pages	4
Journal	Materials Transactions
Volume	48
Issue number	3
DOIs	https://doi.org/10.2320/matertrans.48.451
Publication status	Published - 2007 Mar
Externally published	Yes

Keywords

High pressure
Magnetic entropy
Magnetic phase transition
Magnetocaloric effect

ASJC Scopus subject areas

Materials Science(all)
Condensed Matter Physics
Mechanics of Materials
Mechanical Engineering

Access to Document

10.2320/matertrans.48.451

Cite this

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title = "Magnetic entropy changes of SmMn2Ge2 under high pressure",

abstract = "In order to obtain the information about magnetic states of reentrant ferromagnet, SmMn2Ge2, we have studied the pressure effect on magnetocaloric properties by magnetization measurements under high pressures up to 1.2 GPa in the temperature range from 5 to 300 K. Using the Maxwell relation, we estimated the magnetic entropy change |ΔSM| to be 0.65 JK-1mol-1 at T1 (= 100K) and 0.53 JK -1mol-1 at T2 (= 150K) under 0.1 MPa. By applying pressures up to 0.5 GPa, |ΔSM(T1)| is enhanced (2.0 JK-1 mol-1), while |ΔS M(T2)| is slightly suppressed (0.4 JK-1 mol-1). The obtained values of |ΔSM| were discussed on the basis of a mean field theory using a two-sublattice model.",

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author = "Keiichi Koyama and Shihou Miura and Hironari Okada and Toru Shigeoka and Kazuo Watanabe",

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T1 - Magnetic entropy changes of SmMn2Ge2 under high pressure

AU - Koyama, Keiichi

AU - Miura, Shihou

AU - Okada, Hironari

AU - Shigeoka, Toru

AU - Watanabe, Kazuo

PY - 2007/3

Y1 - 2007/3

N2 - In order to obtain the information about magnetic states of reentrant ferromagnet, SmMn2Ge2, we have studied the pressure effect on magnetocaloric properties by magnetization measurements under high pressures up to 1.2 GPa in the temperature range from 5 to 300 K. Using the Maxwell relation, we estimated the magnetic entropy change |ΔSM| to be 0.65 JK-1mol-1 at T1 (= 100K) and 0.53 JK -1mol-1 at T2 (= 150K) under 0.1 MPa. By applying pressures up to 0.5 GPa, |ΔSM(T1)| is enhanced (2.0 JK-1 mol-1), while |ΔS M(T2)| is slightly suppressed (0.4 JK-1 mol-1). The obtained values of |ΔSM| were discussed on the basis of a mean field theory using a two-sublattice model.

AB - In order to obtain the information about magnetic states of reentrant ferromagnet, SmMn2Ge2, we have studied the pressure effect on magnetocaloric properties by magnetization measurements under high pressures up to 1.2 GPa in the temperature range from 5 to 300 K. Using the Maxwell relation, we estimated the magnetic entropy change |ΔSM| to be 0.65 JK-1mol-1 at T1 (= 100K) and 0.53 JK -1mol-1 at T2 (= 150K) under 0.1 MPa. By applying pressures up to 0.5 GPa, |ΔSM(T1)| is enhanced (2.0 JK-1 mol-1), while |ΔS M(T2)| is slightly suppressed (0.4 JK-1 mol-1). The obtained values of |ΔSM| were discussed on the basis of a mean field theory using a two-sublattice model.

KW - High pressure

KW - Magnetic entropy

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