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Abstract Complex oxides offer rich magnetic and electronic behavior intimately tied to the composition and arrangement of cations within the structure. Rare earth iron garnet films exhibit an anisotropy along the growth direction which has long been theorized to originate from the ordering of different cations on the same crystallographic site. Here, we directly demonstrate the three-dimensional ordering of rare earth ions in pulsed laser deposited (EuxTm1-x)3Fe5O12garnet thin films using both atomically-resolved elemental mapping to visualize cation ordering and X-ray diffraction to detect the resulting order superlattice reflection. We quantify the resulting ordering-induced ‘magnetotaxial’ anisotropy as a function of Eu:Tm ratio using transport measurements, showing an overwhelmingly dominant contribution from magnetotaxial anisotropy that reaches 30 kJ m−3for garnets with x = 0.5. Control of cation ordering on inequivalent sites provides a strategy to control matter on the atomic level and to engineer the magnetic properties of complex oxides.
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This content will become publicly available on May 20, 2025
Synthesis and properties of rare-earth high-entropy perovskite
The high-entropy concept was applied to synthesize a set of rare-earth perovskites REBO3 (RE = La, Pr, Nd, Sm, Eu, Gd) with the B-site occupied by Sc, Al, Cr, Ni, and Fe in equimolar ratios. All samples crystallize in the orthorhombic Pnma space group. Using an extended set of characterization measurements, the effects of multi-component material design and rare-earth selection on the electronic properties are explored. Transport measurements show semiconducting behavior. PrBO3, SmBO3, and LaBO3 show low-temperature magnetic ordering, with the ordering temperature shifting with the moment on the A-site.
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- Award ID(s):
- 2104228
- PAR ID:
- 10524813
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 124
- Issue:
- 21
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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