Strain dependence of the magnetic properties of nm Fe films on W(100)

The thickness dependence of the magneto-elastic coupling B1, the intrinsic film stress, and the magnetic in-plane anisotropy K4 of Fe films on W(100) are measured with an in situ combination of a highly sensitive optical deflection technique with magneto-optical Kerr-effect measurements. We find that both B1 and K4 depend strongly on the Fe film thickness. The thickness dependence of B1 can be described by considering a second order magneto-elastic coupling constant D = GJ/m3 as a strain dependent correction of B1. We tentatively ascribe the deviation of K4 from its bulk value to the tetragonal lattice distortion caused by an effective tensile in-plane strain of 5.3% in the pseudomorphic region and of 0.2% in thicker films