A drop of hyperfine field at Sn in Fe/Cr/Sn/Cr multilayers

The magnetism of the Fe/Cr/Sn/Cr multilayers was studied by first-principles functional theory. The calculations by LAPW and SKKR methods showed that two solutions exist in the $Fe_9/Cr_{14}/Sn/Cr_2$ system. One of them is originated from the antiferromagnetic order in the bulk Cr, and the other is connected with incommensurate spin density wave (ISDW) in Cr. A characteristic feature of this system is realization of ISDW in the Cr film thinner than the half length period of a common ISDW in Cr. In the Cr layers with width lower than a quarter of the wave, the ISDW cannot be the cause of the sharp drop of the HFF at Sn. The calculations of the system $Fe_3/Cr_8/Sn/Cr_8$ with and without allowance for the roughness at the Fe/Cr interface showed that the roughness leads to a significant decrease in the HFF at Sn.