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The magnetic and magnetooptical properties of ([Co.sub.1-x][Ni.sub.x])/Pd multilayers were systematically investigated. The addition of Ni to the Co layer simultaneously decreases the Curie temperature and Kerr rotation angle, but the decrease of the Curie temperature is larger. By controlling the Ni content it is possible to reduce the Curie temperature. The perpendicular magnetic anisotropy energy also decreases with the addition of Ni, but the change is small. The interfacial anisotropy energy and volume anisotropy energy were calculated and discussed. Adding Ni to the Co layer can yield control of magnetic and magnetooptical properties, while maintaining a large effective perpendicular anisotropy energy.

Strongly antiferromagnetically-coupled multilayer magnetic films which have giant magnetoresistance properties are suitable for the manufacture of dual-layer tips. The nature of the material influences the range of interlayer separation associated with antiferromagnetic coupling in the magnetic layers. The saturation remanent magnetization influences the efficiency of film recording.

The determination of the relationship between microstructure and magnetic properties of Co/Pt multilayer films (MLF) reveals that the magnetic properties are highly sensitive to substrate roughness. The Co/Pt MLFs are deposited on substrates with varying roughness. The coercivity is increased and the uniaxial anisotropy is reduced by substrate roughness.

A unified spin-dependent linear transport theory is used to investigate the development of giant magnetoresistance (GMR) of magnetic multilayers and granular solids. The multilayers and solids have short-range scattering caused by impurities in non-magnetic and magnetic regions at interfaces. The GMR is not influenced by the distance between adjacent magnetic regions.

The design of phase-optimized Co/Pt-based trilayer structures to magneto-optically improve the polar Kerr effect was delineated. The device performance was determined as a function of the incident radiation wavelength and incidence angle for the two polarization states. The trilayer structure design scheme used Co-Pt multilayers as the magnetic medium.

Liquid-phase-epitaxy facilitated the growth of multidomain material films, whose temperature-dependent sensitivity characteristics were studied in the zeroth-order diffraction beam. Gd substitution enhanced temperature-dependent sensitivity. The zeroth-order diffraction beam was associated with the boundary displacement process for magnetization reversal.

A two-coercivity model and remanence measurements were used to study the reversal mechanisms in Tb/Fe multilayers. The model delineated the hysteresis form as a function of bilayer numbers. Remanence measurements elucidated energy barrier distribution for two coercive processes.

Sandwiches of Sm-Co/Gd-Co/Sm-Co' and Sm-Co/Co/Sm-Co', manufactured by direct current bias sputtering, are experimentally investigated to determine the magnetization processes. Both sandwiches have different coercive fields. Soft magnetic materials compose the central layer and the thickness ranges from 500 to 5000 angstroms. The magnetic configurations have magnetic moments in the opposite layers and are stabilized.

(Ni81Fe19Ni80Co20)/Ag granular alloy films are investigated to determine their magnetoresistance and structural properties. The films are prepared by annealing of sputtered multilayers having ultrathin magnetic layers. The magnetic resistance is 30% at a temperature of 4.2 K and the saturation field is less than 2 kilo Oersteds.

The suppression of oxidation in Co/Cu multilayer films increases the magnetoresistance ratio. The antiferromagnetic coupling is increased when there is no oxidation of the interfaces between Co and Cu in the multilayers. Oxidation is prevented by the deposition of the film in a low background pressure with an Fe buffer layer.

The magnetoresistance effect in several uranium-based intermetallic compounds at very low temperatures is much larger than the effect occurring in magnetic multilayer systems. This is attributed to the strong 5f conduction electron hybridization in the intermetallic compounds. Giant magnetoresistance effects can be achieved at high temperatures in the same compounds.

The influence of interlayer material and geometry of multilayered systems on the magnetic properties of the systems is studied using temperature-dependent ESR linewidth (delta H(T)). The delta H(T) in CuMn/Al2O3 multilayers is determined and compared with earlier studies performed on CuMn/Cu samples. The results are almost identical except for the fitting parameters which are quantitatively different.

Ion beam sputtering is used to prepare multilayers with 30(Ni-Fe/Cu) bilayers deposited on a 50-angstrom-thick Fe buffer layer. The multilayers exhibit a (100) orientation of Ni-Fe and Cu crystallites. The layer thickness enhances the (100) orientation. The bilayers exhibit soft magnetic properties, coercivity and a relative permeability of 4 Oersteds.

The addition of a second hydrophobic end-group to the hydrophilic chromophore prevents molecular inversion during deposition on a solid substrate. This enables the formation of a 'Z-type' head-to-tail structure for films with up to 100 layers. The newly developed process enables the formation of macroscopic non-centrosymmetric order in Langmuir-Blodgett films.

The dc sputtered Co/Pd multilayer structures (MLS) have been investigated using optical and magnetooptical spectroscopy at room temperature in the photon energy range 0.65-5 eV. The measured Co/Pd MLS polar Kerr rotation and ellipticity show the strong contribution of the Pd magnetooptical activity. The magnetooptical response of the Co/Pd MLS has been simulated by multireflection calculation with magnetooptical Pd contribution. Good agreement between the observed and calculated Kerr spectra has been obtained.

A new detection system, installed on a scanning transmission microscope, enables operation of the microscope in a variety of modes revealing microscopic and magnetic structure and dynamic magnetic phenomena at high spatial and temporal resolution. Experimental observations of magnetic systems including granular Co/Ag, Co and multilayer Fe/Mo thin films are discussed.

Ultrathin films of poly(vinylidene fluoride-trifluoroethylene) copolymers are prepared by a Langmuir-Blodgett technique and the films have displayed ferroelectric properties like hysteresis loops of the polarization and butterfly curves of the ac capacitance versus the applied field. The results have shown that the small signal nonswitching relaxational response resulting in the dielectric permittivity is coupled to the large signal ferroelectric behavior resulting in the hysteresis loops.

A study was conducted to examine the effect of the relative humidity on the properties of ultrathin ferroelectric poly(vinylidene fluoride-trifluoroethylene) films fabricated by the Langmuir-Blodgett technique. The increased relative humidity in the surrounding atmosphere lead to absorption of water molecules by the samples to yield quasi-free charge carriers which could fluctuate between the electrodes of the samples and build a space charge polarization superimposed to the ferroelectric polarization.

The influence of substrates on the pattern formation by Langmuir-Blodgett (LB) transfer is examined by using silicon slides treated by different cleaning processes. The shift in the transfer pressure range for patterning is described with a model of equivalent states and also by considering the effect of microscale water films on the substrates.

The permeation barriers of He, [Co.sub.2] and [N.sub.2] across the glued Langmuir-Blofgett (LB) bilayers in the presence and absence of trapped poly(acrylic acid) (PAA) are described. The analysis proves that the combination of surfactant plus PAA acts as the main barrier for the gas transport in such bilayers.

Langmuir-Blodgett (LB) films of the water-soluble dye phenosafranine (PS) are prepared by its absorption from aqueous dye solution to an arachidic acid (AA) monolayer at the air-water interface. These monolayers can be successfully transferred from the air-water interface to obtain regular and reproducible LB films, as characterized by UV-vis absorption studies.

The electrical characteristics of metal-ferroelectric-insulator-semiconductor structures, where the ferroelectric layer is Langmuir-Blodgett film of a copolymer of 70% vinylidene fluoride and 30% trifluoroethylene are presented. The films were found to exhibit key features of the first order ferroelectric-paraelectric phase transition, which is evident in the thermal hysteresis of the device capacitance in accumulation mode.

The secondary structure of organophosphorus hydrolase (OPH) has been studied with circular dichroism spectroscopy. The effect of pH on the secondary structure of OPH solution has been examined over the pH range from 3.56 to 9.60.

Preparation and characterization of films novel amphiphilic complex, deposited through a modification of the LB technique, and the horizontal lifting or Langmuir-Schafer (LS) method is discussed. In this work homogeneous, densely packed LS films of a novel amphiphilic Ru(II) complex are obtained.

A general solution for elastic deformation of monolithic and multilayered materials due to external loads and moments, mismatch in thermal expansion, and temperature gradients is derived. The stiffness, thickness, thermal expansion coefficient, or thermal gradient was determined by the relationships.

Atomic force microscopy structural analysis show that Langmuir-Blodgett films of class II hydrophobins, HFBI and HFBII from Trichoderma reesei possess highly ordered two-dimensional crystalline structure. Data indicate that the two hydrophobins differ in their structure and properties and that the building blocks of the crystals consist of four hydrophobin molecules.

The inductively coupled rf sputtering was used to design (CoFe)-Si-O/Si-O multilayer nanogranular magnetic thin films for GHz rf circuits. This structural model exhibits 200 real permeability up to 2 GHz with 2.2 m ohm cm resistivity and 2.86 GHz ferromagnetic resonant frequency.

A study of the optical response of (Si/SiO2)(sub m) multilayers, with m ranging from 2 to 8, is presented. The result demonstrates that the (Si/SiO2)(sub m) structures present good optical quality and should be designed to use as one-dimensional photonic crystals with high refractive index contrast and good rejection rate even for small m values.

The thermal stability and read--write performance of longitudinal magnetic recording media with antiferromagnetically coupled layers are investigated. The thermal stability is strongly dependent on the interaction between layers and the anisotropy energy of the stabilizing layer or layers. For media with two coupled layers, the energy barrier is increased by approximately 45% of the anisotropy energy of the stabilizing layer. Although the total thickness is larger compared to a conventional medium with the same remanence magnetization and thickness product Mr[Delta], the resolution is higher and depends on a thickness proportional to the magnetization difference between the layers. With these 'synthetic ferrimagnetic' structures, thermally stable, low [M.sub.r][Delta] and high resolution media are made possible. Index Terms--Antiferromagnetically coupled media, CoCrPtB, longitudinal recording media, thermal stability.

The present paper discusses the interfacial structure and the effect on the magnetic and magneto-optical properties in TbFeCo/Pt multilayer films, in contrast with Fe/Pt multilayers. Both the magnetic and magneto-optical properties are well explained when an interfacial region very similar to an Fe-Pt alloy is assumed. Low angle X-ray diffraction analyses reveal that the Fe-Pt alloy-like interfacial regions are formed mainly on top of TbFeCo layers, but little on Pt layers, w[[Sigma].sub.xy] spectra indicate that polarization of Pt in the interfacial region is different from that in FefPt multilayers. Index Terms--Amorphous TbFeCo alloy, interface, magneto-optical Kerr effect, multilayer, platinum.