Interlayer thickness dependence of the strong 90° coupling in epitaxial CoFe/Mn/CoFe trilayers

Abstract
Trilayers of CoFe/Mn/CoFe(001) have been prepared by molecular beam epitaxy and their magnetic properties measured by magnetometry and ferromagnetic resonance. Very strong near‐90° coupling between the CoFe layers, with no evidence for 180° coupling, was found in all but the thickest Mn‐layer samples. The coupling energy has the form suggested recently for the case when the interlayer itself is antiferromagnetic. An analysis of the ferromagnetic resonance data indicates that the magnitude of the coupling oscillates with the Mn thickness.