Nanoscale physics

Interlayer interactions in magnetic nanostructures with antiferromagnetic FeMn spacer
Lytvynenko Ya.M.1, Polishchuk D.M.1,2, Tykhonenko-Polishchuk Yu.O.1,2, Rostas A.M.3, Kuncser V.3, Kravets A.F.1, Tovstolytkin A.I.1, and Korenivski V.2
1 Institute of Magnetism of the NAS of Ukraine and MES of Ukraine, 36-b Vernadsky Blvd., 03142 Kyiv, Ukraine. 
E-mail: yarina.litvinenko@gmail.com
2 Nanostructure Physics, Royal Institute of Technology, 10691 Stockholm, Sweden.
3 National Institute of Materials Physics, 077125Bucharest-Magurele, Romania.

Recent advances in exploring functionalities of antiferromagnetic (AFM) materials have created and significantly developed the field of antiferromagnetic spintronics, which focuses to understand and effectively control the spin transport or dynamics of antiferromagnetic moments for use in the new generation electronic devices [1-2]. 
In this work, the interlayer exchange interaction in the system “hard ferromagnet (FM) / soft AFM / soft ferromagnet”, Fe/FeMn(t)/Py, transmitted through the AFM layer of FeMn and dependent on its thickness t, will be presented and discussed. Particularly will be considered three modes of exchange interaction in studied multilayers (1) the FeMn spacer has an antiferromagnetic ordering and a strong magnetic anisotropy; (2) the FeMn spacer has an antiferromagnetic ordering, but a relatively weak magnetic anisotropy, which is not enough for an exchange pinning; and (3) when the vast part of the AFM spacer becomes ferromagnetically polarized due to the proximity effect to the Fe and Py layers, and as a result, the outer layers are connected by a direct ferromagnetic exchange interaction. To conclude, the presented results demonstrate a way to the effective control of magnetic dynamics in FM/AFM/FM nanostructures by optimizing AFM spacer and should be of interest in a broad context in the field, together with an outlook of future research and applications of antiferromagnetic spintronics.

1.	Jungwirth T., Marti X., Wadley P. et al. Antiferromagnetic spintronics // Nature Nanotech. – 2016. – 11. – P. 231–241. 
2.	Jungwirth T., Sinova J., Manchon A., et al. The multiple directions of antiferromagnetic spintronics // Nature Phys. – 2018. – 14. – P. 200–203.