STRUCTURE AND MAGNETIC-PROPERTIES OF FE1-XNIX CU INVAR SUPERLATTICES/

We have prepared by sputtering techniques a series of fee [Fe1-xNix/Cu ]X10 superlattices with sublayer thicknesses of 3 nm and with Ni conce ntrations x ranging from 0.26 to 0.54. The use of MgO single-crystal s ubstrates and Cu sublayers in the superlattice growth ensures a well-d efined fcc crystal structure in the Fe-Ni sublayers with a Ni concentr ation as low as 26 at. % and down to liquid helium temperatures. The m agnetization of the Fe-Ni sublayers in the super lattices starts to de viate from the well-known Slater-Pauling curve at 40 at. % Ni, and con tinues to drop until the fcc-bcc transition is completed. A strong dep endence of the magnetization on temperature was also observed for the Fe-Ni sublayers in the Invar range, consistent with the behavior of bu lk Fe-Ni Invar alloys. (C) 1996 American Institute of Physics.