Lattice spacing variations in gold-nickel superlattices

Abstract

Strained layered superlattices of Au and Ni have been grown by sputter deposition. The repeat periodicity, d Au/Ni , of the (111) oriented submicron thick films ranged from 0.78 to 4.60 nm. A variation of lattice spacing, d 111 , in the superlattice growth direction, with the repeat periodicity of the superlattice has been measured using standard theta/2theta CuKa x-ray diffraction. A minimum in (1/d 111 ) was found at d Au/Ni equal 2 nm, with increasing values of (1/d 111 ) above and below this repeat period. This variation of (1/d 111 ) with d Au/Ni , reported for the first time for the Au/Ni system, is anticipated in thosenoble/transition metal superlattice systems which exhibit the supermodulus effect“.