Formation of induced anisotropy in amorphous Sm-Fe based thin films by field sputtering

Induced anisotropy with a large energy of 6x10(4) J/m(3) is formed in an amorphous Sm-Fe based thin film by sputtering under an applied magnetic field of 500-600 Oe. The induced anisotropy results in a large anisotropy in magnetostriction, a strain anisotropy ratio reaching as high as 35, although intrinsic magnetostriction is affected only slightly. The large strain anisotropy allows one to realize a large strain in a particular direction and, hence, it is of significant practical importance. Induced anisotropy is also found to be formed by postannealing under applied magnetic field, but the magnitude of anisotropy energy formed is very small. (C) 2000 American Institute of Physics. [S0021-8979(00)16508-9].