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The measurements of magnetostriction constant λs of Co/C multilayers have been performed at room temperature using strain modulated ferromagnetic resonance. The dependence of λs on the inverse Co layer thickness is interpreted as arising due to the volume and interface interactions. It is suggested that magnetostriction in Co/C systems arises mainly from dipole-dipole interaction.

The saturation magnetostriction constant lambda /sub s/ has been measured at room temperature in Co/Ag multilayer films prepared by evaporation in ultrahigh vacuum. It was found that in addition to the surface magnetostriction term, an additional one due to reduced symmetry of the magnetoelastic interaction should be incorporated to explain the peculiar dependence of lambda /sub s/ on the thickness of the Co layer. The dependence of the anisotropy constant K/sub u/ on the Co-layer thickness in the films investigated resembles the dependence of lambda /sub s/, indicating that the same mechanisms are important in both cases. The results obtained are shown to be related to the reduced symmetry in the nanometer-scale multilayer films. >

EPR measurements have been performed in the temperature range 4.2-295 K on a polycrystalline sample of the linear chain system MnC2O4.2D2O. The temperature dependence of the width of the resonance line has been analysed in terms of the available theory for a one-dimensional antiferromagnet.

The influence of the Mo content in (Gd 1− x Co x ) 1− y Mo y thin amorphous films was studied. Samples were prepared by the rf sputtering technique with x from 0.66 to 0.97 and y from 0.01 to 0.14. It was found that molybdenum influences the saturation magnetization, the g -factor and the uniaxial anisotropy field. Also surface modes in spin wave resonance in thin films (Gd 1− x Co x ) 1− y Mo y x = 0.85−0.94, y = 0.01−0.12 were studied. The surface anisotropy constant was determined from the surface inhomogeneity (SI) model [1]. The fitted K s values [2] agree with theoretically predicted ones. For some of our samples the best fit between model and experimental data was obtained when the surface anisotropy energy was assumed as a superposition of the uniaxial anisotropy term and a biaxial anisotropy term. The study of the influence of temperature and Mo content on the value of surface anisotropy constants shows that: 1. i) There is a critical temperature when the surface uniaxial anisotropy constant changes its character; 2. ii) an increasing Mo content makes the temperature dependence of the surface anisotropy constants more stabilized.

The EPR spectrum of Gd3+ ions diluted (0.5% and 0.1%) in powdered samples of the high-Tc(Tc-92 K) superconductor Y1Ba2Cu3Ox has been measured at X-band in the temperature range 4.2-300 K. It was shown that the EPR spectrum exhibits significant changes in g-shift, thermal broadening and intensity well below Tc. The results are analysed in terms of existing theoretical models.

Spin wave excitations in thin amorphous GdCoMo films deposited by r.f. sputtering were studied in order to determine the exchange energy constant. The spin wave resonance spectra were taken at temperatures ranging from 4 to 300 K which allowed us to find the temperature dependence of the exchange energy constant for GdCoMo films.

The theory of temperature and magnetic field dependence of magnetostriction in amorphous thin films has been developed for the following models: pair-ordering model, random anisotropy model and columnar structure model. Detailed calculations have been performed within the molecular field approximation and spin-wave approximation.

A new preparation method of thin CdCr2Se4 : In films by vacuum evaporation technique is proposed. We report and analyse the temperature dependence of magnetization and the effect of Cr2+ and Cr+4 impurity ions on the FMR linewidth. Also the electrical transport properties of these films are studied.

The forced magnetostriction arising from the magnetic field dependence of the volume and linear magnetostriction of amorphous alloys is calculated within the random anisotropy model. It is shown that forced magnetostriction in amorphous materials is determined by several mechanisms with different origins.

The theory of stress annealing anisotropy and magnetostriction as well as stress - dependent saturation magnetostriction in amorphous alloys is developed, Two models are considered: the pair - ordering model and the random anisotropy model, it is shown that dependence of saturation magnetostriction on stress can be explained only in terms of pair - ordering model. The observed stress - induced effects are shown to be related to microstructural parameters of amorphous alloys.

Random anisotropy model of magnetoelastic interaction is considered from both classical and quantum point of view. In both cases the exchange interaction is treated in the molecular field approximation. It was shown that the temperature dependence of the effective magnetoelastic tensor components has a complicated character, often different from the one predicted by the single-ion or two-ion theories.

In this paper the investigations of magnetic and magnetoelastic properties of Fe/Si multilayers are presented. The multilayers have been grown by dc sputtering on the single - crystal GaAs substrates. Ferromagnetic resonance (FMR) measurements were performed at the frequency of 9.4 GHz and in the temperature range from liquid helium to room temperature before and after illumination with 514nm light. The magnetostriction constant of investigated films has been measured at room temperature by strain modulated ferromagnetic resonance (SMFMR) method. An attention is given to the effect of the interface on the observed effective saturation magnetostriction. The FMR and SMFMR measurements mostly revealed the contribution from interface to the observed spectra. The results were analyzed taking into account both the alloying effects and the intrinsic surface anisotropy and magnetostriction. It was shown that in the case of Fe/Si multilayers the effect of alloying prevails.

Multilayer Ni-C films have been prepared using d.c. triode sputtering with a fixed C layer of 2 nm thick and wlth Ni layer varying from 5 to 100 nm thick. The C layer is amorphous and the structure of Ni layer is hexagonal for 5nm thick but becomes f.c.c. when the thickness is above 6 nm. The magnetization is strongly reduced which is attributed to the presence of nonmagnetic layers at each interface. These layers could be Ni 3 C. The magnetostriction of the investigated films was measured at room temperature using the strain modulated ferromagnetic resonance method. The square dependence of magnetostriction constant on saturation magnetization was obtained.