MAGNETIC-ANISOTROPY AND GIANT MAGNETOSTRICTION OF AMORPHOUS TBDYFE FILMS

The influence of internal stress on the magnetic anisotropy and the ma gnetostriction was investigated in sputter-deposited amorphous (Tb0.27 DY0.73)(0.42)Fe-0.58 films. Films with tensile stress show in-plane an isotropy and giant magnetostriction of lambda(parallel to)=400X10(-6) at 1 T measured in a field parallel to the film plane at room temperat ure. The magnetostriction rises rapidly to lambda(parallel to)=200X10( -6) at 0.05 T and the coercivity is less than 0.01 T. On the other han d films with compressive stress show perpendicular anisotropy and stil l higher magnetostriction of lambda(parallel to)=540x10(-6) at 1 T; ho wever, this is by far a slower increase of magnetostriction at small f ields. This different behavior is explained by considering the nature of magnetization processes, i.e., domain-wall motion and spin rotation .