Nanocomposites and Nanomaterials
Thermal switching of indirect interlayer exchange coupling in Fe/FeCr/Fe multilayers
Polishchuk D.M.1,2, Tykhonenko-Polishchuk Yu.O.1,2 Polek T.I.1, Kravets A.F.1, Yaremkevich D.D.1, Pogorily A.M.1, Korenivski V.2
1 Institute of Magnetism of the NAS of Ukraine and the MES of Ukraine, Blvd. Vernadsky, 36b, Kyiv-03142, Ukraine. 
E-mail: polek.taras@gmail.com
2 Nanostructure Physics, Royal Institute of Technology, Roslagstullsbacken, 21, Stockholm-10691, Sweden

A new concept of thermomagnetic switching in magnetic multilayer nanostructures with the spacers of dilute ferromagnetic alloy was proposed, in which, depending on temperature, indirect and direct interlayer exchange coupling are combined and competing [1]. With a slight change in temperature, the direct exchange interaction responsible for the ferromagnetic ordering in the structure is switched off, and the indirect exchange interaction (also known as RKKY) responsible for antiferromagnetic ordering is activated, which leads to a thermomagnetic switching of the magnetic and resistive states of the structure. 
On/off IEC switching in a Fe/FeCr/Fe-based system have been demonstrated and thermal switching widths as small as 10–20K have been obtained, essentially in any desired temperature range, including at or just above room temperature. The switching occurs in the absence of the applied magnetic field, as opposed to the previously developed thermomagnetic Curie switch [2].
The demonstrated effect of thermally controlled indirect exchange interaction adds a new degree of freedom in the design of future spintronic devices such as magnetic random access memory and spin oscillators.

1.	Polishchuk D.M., Tykhonenko-Polishchuk Yu.O., E. Holmgren, Kravets A.F., Korenivski V. Thermally induced antiferromagnetic exchange in magnetic multilayers // Phys. Rev. B –2017. -96, -P. 104427.
2.	Kravets A.F., Timoshevskii A.N., Yanchitsky B.Z., Bergmann M.A., Buhler J., Andersson S., Korenivski V. Temperature-controlled interlayer exchange coupling in strong/weak ferromagnetic multilayers: A thermomagnetic Curie switch // Phys. Rev. B –2012. -86, -P. 214413.