Spin density wave in epitaxial Cr(001)/Sn and Cr(001)/Au multilayers with nonmagnetic spacer layers

The magnetic structures of epitaxial Cr(001) thin films with periodic monat omic Sn or Au spacer layers, [Cr(8.0 nm)/Sn(0.2 nm)]x30, [Cr(4.0 nm)/Sn(4.0 nm)]x60 and [Cr(8.0 nm)/Au(0.2 nm)]x30 multilayers, were investigated by n eutron diffraction. A commensurate antiferromagnetic structure was stabiliz ed in all these multilayers at 300 K. It was found that highly distorted si nusoidal spin density waves (SDWs) with the propagating vector normal to th e film plane were formed in the multilayers with Cr(8.0 nm) at 20 K. The SD W period was twice as large as that of the multilayer. The antinodes of the SDW are probably pinned at the Cr/Sn or Cr/Au interfaces so as to form SDW s with a period much longer than that of bulk Cr.