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Ill., graph. Darst.

graph. Darst.

Ill., graph. Darst.

We have prepared multilayered compositionally modulated films by alternately depositing Co and Nb layers of 50 and 24 A nominal thickness, respectively. Two e -beam evaporation systems in ultra high vacuum were used. Magnetization and B-H loop measurements were done at 293 K. Ferromagnetic resonance was observed at 9.79 GHz using cavity techniques and as a function of frequency in the range 4–14 GHz using a planar microwave structure. The magnetization 4 πM =13 kG is found to be lower than the Co bulk value. The observed frequency dependence of the linewidth in the parallel orientation can be interpreted. Possible explanations for the reduction of 4π M are discussed.

We have prepared Ni-Ag multilayers and studied their magnetization (M) (68 - 293 K) and FMR properties (290 K). The Ag layer thickness (t Ag) was kept constant at 5 nm and that of Ni (t Ni) varied from 0.7 to 10 nm. At 4 K, M decreases slightly from the bulk value but remains much higher than that reported so far in other systems. We attribute this to the presence of Ag in the pores of thin layers of Ni and their mixing which leads to an increase in Ni moment. FMR results are shown to indicate to relatively high M for t < 3 nm where no anisotropy expected. The large increase in the line width in these cases also confirms the presence of magnetic inhomogeneities.