TEMPERATURE-DRIVEN INPLANE ANISOTROPY REORIENTATION TRANSITION IN FE(110) FILMS

The competition between surface and volume magnetic anisotropy in ultr a-thin films may induce a dramatic thickness and temperature dependenc e of the anisotropy. Whereas the former has been studied extensively, only a few reports have appeared on the latter for in-plane anisotropy . We have analysed such an in-plane reorientation in a W(110)/Fe(110)( 60 A)/W(110) film, which occurs because of the differences in the temp erature dependencies of the various contributions involved in the tota l anisotropy. The second-order interface anisotropy constant is deduce d for this system (100 to 300 K) from total anisatropy measurements an d subtraction of bulk contributions. The thermal variation of the inte rface anisotropy constant with the reduced spontaneous magnetization m (s) is found to follow an m(s)(13/2) law. Phase diagrams are derived.