Metamagnetic transition, magnetocaloric effect and electronic structure of the rare-earth anti-perovskite SnOEu3

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:501

Article

Guillou, F.^1,2  Paudyal, D.¹  Mudryk, Y.¹  Pathak, A. K.^1,3  Smetana, V⁴  Mudring, A-, V⁴  Pecharsky, V. K.^1,5 

[1] Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA

[2] Inner Mongolia Normal Univ, Inner Mongolia Key Lab Phys & Chem Funct Mat, Hohhot 010022, Peoples R China

[3] SUNY Buffalo State, Dept Phys, Buffalo, NY 14222 USA

[4] Stockholm Univ, Dept Mat & Environm Chem, Phys Mat Chem, Svante Arrhenius Vag 16c, S-10691 Stockholm, Sweden

[5] Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA

关键词: Rare-earth alloys;    Metamagnetism;    Anti-perovskites;    Magnetocaloric effect;    Band topology;    High-pressure;   

DOI  :  10.1016/j.jmmm.2020.166405

来源: Elsevier

【 摘 要 】

Rare-earth anti-perovskites with oxygen are an interesting magnetic materials family at the boundary between intermetallics and oxides, they however remain largely unexplored. Here, magnetic and heat capacity investigations, as well as density functional theory (DFT) calculations, were carried out on SnOEu3. At low magnetic field (B <= 0.5 T), a Neel temperature separates antiferromagnetic and paramagnetic phases at 31 K. When applying higher magnetic field below the Neel temperature, successive transformations toward a ferromagnetic state via a number of intermediate canted magnetic structures are observed and are associated with only modest latent heat and transition entropy. High-pressure magnetic measurements confirm the stable divalent state of Eu up to 1.05 GPa. A direct magnetocaloric effect progressively increases with applied magnetic field above the Neel temperature, reaching -16 J kg(-1) K-1 for Delta B = 7 T. On the other hand, the inverse magnetocaloric effect of the field-induced transition below T-N saturates at similar to+ 5 J kg(-1) K-1. DFT calculations support magnetic instabilities observed experimentally in SnOEu 3 and reveal an unusual exchange mechanism and band topology near the Fermi level.

【 授权许可】

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