INFLUENCE OF THE TOP AND BOTTOM INTERFACE ON PERPENDICULAR MAGNETIC-ANISOTROPY IN TB-FE-AG MULTILAYERS

Mossbauer spectroscopy (CEMS), vibrating-sample magnetometry and the p olar magneto-optic Kerr effect (MOKE) have been employed to investigat e the effect of either ''top'' (Tb-deposited-on-Fe) or ''bottom'' (Fe- deposited-on-Tb) interfaces, or of both types of interfaces, on magnet ic properties of UHV-grown Tb-bcc-Fe-Ag multilayers. All samples devel op perpendicular Pe-spin texture, perpendicular magnetic anisotropy, p olar remanence, and large polar coercivities upon cooling; however, th e T-dependence is found to be different for different types of interfa ces. The remanent-magnetized state of the Fe-layers at low T is either nearly a perpendicular single-domain state or a nearly perpendicular multidomain state, bath states being characterized by canted Fe-spins or canted easy axes (cone state). The shape of MOKE hysteresis loops i s found to be wavelength dependent. Qualitatively, all effects may be correlated with differences in Tb-Pe interface roughness.