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arXiv · 1401.8148

First-principles calculation of the instability leading to giant inverse magnetocaloric efects

Denis Comtesse·Markus E. Gruner·Vladimir V. Sokolovskiy·Vasiliy D. Buchelnikov·Anna Grünebohm·Raymundo Arroyave·Navdeep Singh·Tino Gottschall·Oliver Gutfleisch·Volodymyr Chernenko·Franca Albertini·Sebastian Fähler·Peter Entel
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Abstract

The structural and magnetic properties of functional Ni-Mn-Z (Z = Ga, In, Sn) Heusler alloys are studied by first-principles and Monte Carlo methods. The \textit{ab initio} calculations give a basic understanding of the underlying physics which is associated with the strong competition of ferro- and antiferromagnetic interactions with increasing chemical disorder. The resulting $d$-electron orbital dependent magnetic ordering is the driving mechanism of magnetostructural instability which is accompanied by a drop of magnetization governing the size of the magnetocaloric effect. The thermodynamic properties are calculated by using the \textit{ab initio} magnetic exchange coupling constants in finite-temperature Monte Carlo simulations, which are used to accurately reproduce the experimental entropy and adiabatic temperature changes across the magnetostructural transition.

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Denis Comtesse, Markus E. Gruner, Vladimir V. Sokolovskiy, Vasiliy D. Buchelnikov, Anna Grünebohm, Raymundo Arroyave, Navdeep Singh, Tino Gottschall, Oliver Gutfleisch, Volodymyr Chernenko, Franca Albertini, Sebastian Fähler, Peter Entel. 2014-01-31. First-principles calculation of the instability leading to giant inverse magnetocaloric efects. https://doi.org/10.1103/physrevb.89.184403

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