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arXiv · 2205.04960

Road to zero-field antiferromagnetic skyrmions in a frustrated AFM/FM heterostructure

M. Mohylna·V. Tkachenko·M. Žukovič
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Abstract

We demonstrate a mechanism of significant reduction, including complete elimination, of the external magnetic field required for the stabilization of a skyrmion lattice (SkX) phase in a frustrated triangular Heisenberg antiferromagnet (AFM) with the Dzyaloshinskii-Moriya interaction. It is achieved by coupling of such a AFM plane to a reference ferromagnetic (FM) layer, which generates an effective field cooperating with the external magnetic field. If the FM layer shows some axial single-ion anisotropy then the effective field can also be generated in zero external field due to a spontaneous FM long-range ordering. Then a sufficiently large interlayer coupling can fully substitute the external magnetic field and the SkX phase in the AFM layer can be stabilized even in zero external field.

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M. Mohylna, V. Tkachenko, M. Žukovič. 2022-05-10. Road to zero-field antiferromagnetic skyrmions in a frustrated AFM/FM heterostructure. https://doi.org/10.1016/j.physleta.2022.128350

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