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The method of production of a particulate medium from the decomposition of cobalt nitride precursor films was described. The process involved two stages: reactive sputtering to develop a precursor film of cobalt nitride and rapid thermal processing in vacuum. The precursor film disassociated leaving the required dispersion of cobalt particles. Samples with saturation magnetization between 60% and 20% of bulk cobalt exhibit isotropic magnetic properties in-plane with high remanence and coercivities.

A technique to sense the magnetic characteristics of the individual layers of a multi-layer structure is demonstrated. It detects the interaction between a thermal wave and the magnetization dependent thermal transport properties of the medium. A modulated laser beam is used to generate a thermal wave at the surface of a thin film sample and launch it into the medium. The amplitude and phase of the wave are modulated by the thermal properties of the medium as it propagates. Initial results for a AgNiFe magnetic thin film under a non-magnetic overlayer have successfully measured the magnetization dependent thermal conductivity. The measurements agree well with those obtained from the magnetization dependent resistivity.

The nonlinear magneto-optic behaviour of thin films of PtMnSb in the transverse Kerr configuration has been investigated, and circular dichroism measurements of Reif and colleagues have been extended to other angles of incidence. Asymmetry is shown to originate in odd and even signals in the sample magnetization. Magneto-optic effects were measured to at least an order of magnitude higher in the SHG field that in the normal linear field.

The optical constants of a magnetic material may be determined by simultaneous measurement of the fractional changes in both the reflectance and the absorption introduced in the magneto-optic interaction when the sample magnetisation is reversed between saturated states. The magnetisation dependent photometric parameters, R and A, are determined without absolute measurement of optical intensity.

Magneto-optical measurements of the anisotropy of homogeneous [Dy.sub.18][Fe.sub.82], films as a function of thickness (134.0-13.4 nm) confirm that the perpendicular anisotropy disappears when films are less than 60nm thick. Since, the range of films exhibits both out of plane and in-plane anisotropy, both the polar Kerr effect and the transverse Kerr effect were used to determine the anisotropy. At about 60nm the perpendicular anisotropy [Mathematical Expression Omitted] the shape anisotropy ([K.sub.s]=2[Pi][[M.sub.s].sup.2]).

Comparison is made between the experimental and theoretical behaviour of the magneto-optical properties of a series of Co-Si[O.sub.2] films in which the volume fraction q occupied by the particles is varied between 0.4 and 0.8. A modified Maxwell Garnett model is used to compensate for both the surface oxidation of the cobalt particles and the reduced electron mean free path.

The magnetic and structural properties of Ba[Fe.sub.12][O.sub.19] films prepared by sputtering are compared with samples deposited using laser ablation deposition (LAD). Both techniques yield as-deposited films that are without crystal structure and consequently non-magnetic. The development of crystal structure and associated magnetic properties after rapid thermal processing (RTP [1]) and ultra-rapid thermal processing using a C[O.sub.2] laser is presented. Early results indicate that control of the oxygen content of the material is of critical importance during both preparation and subsequent processing. Provided this control is present a material with a significant perpendicular magnetic anisotropy can result from very rapid thermal processing.

Kerr polarimetry and ellipsometry measure magnetooptical and optical constants of Pr-substituted TbFeCo films placed between SiN passivation layers developed from rf magnetron sputtering process. The Pr component decreases magnetooptic (MO) film thickness, increases ellipticity of films and degrades the MO activity of the films. MO and optical constants evaluated are used in trilayer structure modeling for MO media system usage.

Pt level deficiency increases coercivity and adjustment in rapid thermal processing (RTP) time and composition regulates the crystalline texture of the PtMnSb films. Coercivity is independent of the crystalline texture and dependent on formation of MnSb stages in the PtMnSb films. Coercivity is independent of the crystalline texture and dependent on formation of MnSb stages in the PtMnSb microstructure. Pt deficiency reduces polar Kerr rotational properties in the films.

Substitution of small concentrations of Fe in barium ferrite thin films by Co, Mn, Cr and Ni in using a multitarget scanning cosputtering process and rapid thermal processing results in enhanced magneto-optical properties as indicated by significant increase in polar Kerr rotation at shorter wavelengths. The magnetic properties remain unaltered in the case of Co and Ni substitution. Mn and Cr reduced the magnetic anisotropy.

The luminescences of CaS doped with Eu(super 2+) are studied under hydrostatic pressure at room temperature. Besides the main Eu(super 2+) emission peak, a low-energy peak emerges with increasing pressure and the results are explained in terms of a single configuration coordination model.