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

Journal Article · 06 January 2020 · Journal of Magnetism and Magnetic Materials

DOI: https://doi.org/10.1016/j.jmmm.2020.166405 · OSTI ID:1591616

Guillou, F. ^[1]; Paudyal, D. ^[2]; Mudryk, Y. ^[2]; Pathak, A. K. ^[3]; Smetana, V. ^[4]; Mudring, A. -V. ^[4]; Pecharsky, V. K. ^[5]

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1. Ames Lab., Ames, IA (United States); Inner Mongolia Normal Univ., Hohhot (China)
2. Ames Lab., Ames, IA (United States)
3. Ames Lab., Ames, IA (United States); State Univ. of New York (SUNY), Buffalo, NY (United States)
4. Stockholm Univ. (Sweden)
5. Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States)

Rare-earth anti-perovskites with oxygen are an interesting magnetic materials family at the boundary between intermetallics and oxides, however they 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 Néel temperature separates antiferromagnetic and paramagnetic phases at 31 K. When applying higher magnetic field below the Néel 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 Néel temperature, reaching -16 J kg^–1 K^-1 for ΔB = 7 T. On the other hand, the inverse magnetocaloric effect of the field-induced transition below T_N saturates at ~+5 J kg^-1 K^-1. DFT calculations support magnetic instabilities observed experimentally in SnOEu₃ and reveal an unusual exchange mechanism and band topology near the Fermi level.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC02-07CH11358
• OSTI ID: 1591616
• Report Number(s): IS-J--10131
• Journal Information: Journal of Magnetism and Magnetic Materials, Journal Name: Journal of Magnetism and Magnetic Materials Journal Issue: C Vol. 501; ISSN 0304-8853
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English