Low-temperature nuclear orientation of160Tb in Tb/Fe multilayers

Magnetic moment direction of Tb in [Fe(40 A)/Tb(x A)]30 multilayers (x=20 and 10) has been studied by the low-temperature nuclear orientation technique in the temperature range of 5–50 mK and in the external magnetic field (Bext) range of 0–1 T, applied along the sample plane. The γ-ray anisotropy of the 299 keV160Tb line was monitored. The perpendicular magnetic anisotropy (PMA) of the Tb magnetic moments has been found at zero Bext for both systems. The PMA effect increased when the Tb layer thickness decreased.