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Granular cermet films (Fe[sub 50]Co[sub 50])[sub x]–(Al[sub 2]O[sub 3])[sub 1-x] fabricated using the electron-beam coevaporation technique at oblique incidence of FeCo and alumina atom fluxes have been found to exhibit both oblique and in-plane uniaxial magnetic anisotropy. This anisotropy first appears just below the percolation threshold due to a magnetic coupling of particles taking place at a certain stage of their growth and coalescence. The FeCo content x varied from 0.07 to 0.49. A simple model of the film microstructure is presented based on the results of magnetization measurements and ferromagnetic resonance at intermediate (9.4 GHz) and high (94 GHz) frequencies. At 94 GHz the concentration dependence of the effective anisotropy field follows the solid solution law, since then the magnetic field is sufficient to magnetize the films close to saturation. The 9.4 GHz data points deviate from the solid solution line below the percolation threshold due to both modification of the resonance fields by intergranular interactions in nonsaturated films and the reduction of the average magnetization of granules, comparing to the saturation magnetization, at room temperature. Different mechanisms of line broadening observed at frequencies used in experiments are also discussed. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The average value of the magnetocrystalline anisotropy field, H[sub k], is an important parameter for the characterization of magnetic recording media but is difficult to measure accurately due in part to the effect of interactions between the grains. In order to evaluate H[sub k] we have studied two model CoCrPtTa magnetic films using a number of complementary techniques: high field ferromagnetic resonance (FMR) (35.0–45.0 kOe), low field (<20 kOe) vector vibrating-sample magnetometry and torque magnetometry. The FMR measurements were performed at a number of discrete frequencies in the range 75–93 GHz using a new quasi-optical spectrometer developed at the University of St. Andrews. The values of H[sub k] derived by FMR (10.8 kOe) are approximately 10% greater than those obtained from conventional magnetometry (9.6 kOe). This difference is believed to be due to the presence of intergranular exchange coupling which reduces the measured value of anisotropy when the applied field is not sufficiently large to completely align the magnetic moments. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

[sup 59]Co nuclear magnetic resonance (NMR) measurements have been undertaken to determine the local atomic environment of Co in Co/V multilayers, previously studied by magnetometry. These NMR measurements provide confirmation, on a local atomic scale, of the results deduced from the earlier magnetization study. Co/V multilayers show considerable interfacial mixing with a magnetically dead, vanadium rich layer penetrating approximately 2 Å into an adjoining Co layer. The presence of this dead layer has the effect of modifying the hyperfine field experienced by the Co nuclei at a distance of several atomic planes from the interface. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A [sup 55]Mn nuclear magnetic resonance (NMR) study of the La[sub 1-x]Ca[sub x]MnO[sub 3] system, 00.5 the spin echo spectra contain resonance lines corresponding to both the microscopic ferromagnetic and antiferromagnetic regions. A resonance line near 380 MHz, which is similar to that of the spectrum of the ferromagnetic and metallic compounds (0.2

Deals with a study wherein cobalt nuclear magnetic resonance studies of the effect of annealing molecular beam epitaxy on grown cobalt and copper multilayers have been undertaken. Methods; Results; Discussion.

Studies the nuclear magnetic resonance measurements of cobalt and manganese. Magnetic properties of manganese; Details on the experiment; Discussion on the results of the study.

Presents a study which measured the pressure dependence of the Curie point and forced magnetorestriction of yttrium(cobalt[sub1-x]aluminum[subx])[sub2]. Experiment; Results and discussion; Conclusion.

Presents a study which performed a nuclear magnetic resonance (NMR) of expanded lattice permanent magnet nitrides and carbides at high pressure. Experimental methods; Examination of the NMR spin-echo spectra of the individual site ytrrium and samarium hyperfine fields in ytrrium[sub2]iron[sub17]A[subx], where A is a light interstitial element, and samarium[sub2]iron[sub17; Results and discussion.

Presents an initial study of the field of dependence of [sub59]cobalt nuclear magnetic resonance for cobalt/copper(111) multilayer films grown by molecular beam epitaxy. Introduction to the technique of spin echo nuclear magnetic resonance in ferromagnetic materials; Experimental setup; Analysis of the zero applied field spectrum.

Focuses on the nuclear magnetic resonance (NMR) of molecular beam epitaxially grown Co-Cu superlattices that exhibit large magnetoresistance. Peak of the main line of the cobalt NMR for the copper-based samples; Factor attributed to the average strain in the cobalt layers; Indication of the NMR measurements.

Investigates the magnetic properties of epitaxial bcc cobalt films using the surface magneto-optic Kerr effect. Details on the experiment; Equipment used in the polarized neutron reflection measurements.