Orthogonal interlayer coupling in an all-antiferromagnetic junction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35764620.
- Also identified by DOI 10.1038/s41467-022-31531-w and PMC identifier 9240048.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
In conventional ferromagnet/spacer/ferromagnet sandwiches, noncollinear couplings are commonly absent because of the low coupling energy and strong magnetization. For antiferromagnets (AFM), the small net moment can embody a low coupling energy as a sizable coupling field, however, such AFM sandwich structures have been scarcely explored. Here we demonstrate orthogonal interlayer coupling at room temperature in an all-antiferromagnetic junction Fe<sub>2</sub>O<sub>3</sub>/Cr<sub>2</sub>O<sub>3</sub>/Fe<sub>2</sub>O<sub>3</sub>, where the Néel vectors in the top and bottom Fe<sub>2</sub>O<sub>3</sub> layers are strongly orthogonally coupled and the coupling strength is significantly affected by the thickness of the antiferromagnetic Cr<sub>2</sub>O<sub>3</sub> spacer. From the energy and symmetry analysis, the direct coupling via uniform magnetic ordering in Cr<sub>2</sub>O<sub>3</sub> spacer in our junction is excluded. The coupling is proposed to be mediated by the non-uniform domain wall state in the spacer. The strong long-range coupling in an antiferromagnetic junction provides an unexplored approach for designing antiferromagnetic structures and makes it a promising building block for antiferromagnetic devices.