Perprendicular magnetic anisotropy of Tb magnetic moments in Tb/Fe multilayers

摘要

The direction of the magnetic moment of Tb in Fe(40A)/Tb(x A) (x=10 and 20) multilayers has been studied using the low-temperature nuclear orientation technique in the temperature range 5-50 mK and in the external magentic field range B_ext =0-8.5 T, with B_ext applied along the sample plane. The anistropy of the 299 keV ~160Tb gamma-line was monitored in three directions with respect to B_ext and the sample plane. The perpendicular magnetic anisotropy (MA) of the Tb magnetic moments has been foound at zero B_ext for both systems. The PMA effect is increased when the Tb layers are thinner. An application of B_ext turned the Tb magnetic moments towards the sample plane, without reaching a full alignment even at B_ext = 8.5 T.