New Type of Oscillatory Exchange Coupling Induced by Ordering in the Magnetic Layers

Abstract

We found that formation of an ordered phase in alloyed magnetic layers induces new periods of exchange coupling oscillations in metallic multilayer systems. We studied on an ab initio level the case of $c(2\ifmmode\times\else\texttimes\fi{}2)$ ordering of random C${\mathrm{o}}_{50}$F${\mathrm{e}}_{50}$(001) magnetic slabs embedded in fcc Cu. The origin of the new periods can be correlated to critical points of the spacer Fermi surface folded down to the Brillouin zone corresponding to the $c(2\ifmmode\times\else\texttimes\fi{}2)$ superlattice.