MAGNETIC-STRUCTURE OF FE CR FE TRILAYERS

The magnetic structure of Cr films deposited on single crystal Fe(001) /GaAs(001) substrates is investigated by soft x-ray magnetic circular dichroism (SXMCD) of the L2 and L3 absorption edges. We find that 0.25 ML Cr coverages result in Cr moments aligned with each other and anti aligned to the underlying Fe moment direction. The Cr moment is measur ed to be 0.6 +/- 0.2 mu(B). Additional Cr deposition results in a mono tonically reducing averaged moment consistent with the island growth o f ferromagnetic Cr sheets of a single layer, antialigned with adjoinin g sheets. SXMCD measurements of the trilayer structures clearly show t he antiferromagnetic coupling of the two Fe films through the interlyi ng Cr film.