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arXiv · 1501.01659

Effects of pressure on the magnetostructural and magnetocaloric properties of isostructurally alloyed (MnNiSi)1-x(FeCoGe)x

Tapas Samanta·Daniel L. Lepkowski·Ahmad Us Saleheen·Alok Shankar·Joseph Prestigiacomo·Igor Dubenko·Abdiel Quetz·Iain W. H. Oswald·Gregory T. McCandless·Julia Y. Chan·Philip W. Adams·David P. Young·Naushad Ali·Shane Stadler
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Abstract

The isostructural alloying of two compounds with extremely different magnetic and thermo-structural properties has resulted in a new system, (MnNiSi)1-x(FeCoGe)x, that exhibits extraordinary magnetocaloric properties with an acute sensitivity to applied hydrostatic pressure (P). Application of hydrostatic pressure shifts the first-order phase transition to lower temperature ($Δ$ T=-41 K with P=3.43 kbar) but preserves the giant value of isothermal entropy change (-$Δ$S$\max$=143.7 J/kg K for a field change of ΔB=5 T at atmospheric pressure). Together with the magnetic field, this pressure-induced temperature shift can be used to significantly increase the effective relative cooling power.

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Tapas Samanta, Daniel L. Lepkowski, Ahmad Us Saleheen, Alok Shankar, Joseph Prestigiacomo, Igor Dubenko, Abdiel Quetz, Iain W. H. Oswald, Gregory T. McCandless, Julia Y. Chan, Philip W. Adams, David P. Young, Naushad Ali, Shane Stadler. 2015-01-07. Effects of pressure on the magnetostructural and magnetocaloric properties of isostructurally alloyed (MnNiSi)1-x(FeCoGe)x. https://arxiv.org/abs/1501.01659

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