Stabilization of metastable expanded face-centered-tetragonal manganese

The structural and magnetic properties of Mn prepd. on single cryst. face-centered-tetragonal (fct) Co(001) were investigated. Mn grows coherently up to at least 50 monolayers (ML) and adopts a metastable expanded fct(001) phase [c/a=1.055(5)]. This new fct-Mn phase was recently predicted theor. by Hafner and Spisak [Phys. Rev. B 72, 144420 (2005)]. Studies of magnetic Mn/Co interface exchange interactions prove the room temp. antiferromagnetic state for thicknesses above 2.5 ML. The magnetic anisotropy of the thin Mn is high enough to induce a significant exchange anisotropy for Mn thicknesses as low as 6 ML. The potential of fct-Mn to become a novel model system for systematic studies on the exchange interactions at antiferromagnet/ferromagnet interfaces is discussed. [on SciFinder (R)]