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The structural, magnetic, electric transport and specific heat properties are studied on lightly Cr-doped molybdates Sr[Mo.sub.1-x][Cr.sub.x][O.sub.3] (0

Single domain uniformly magnetized CoPt are used to probe magnetic force microscopy (MFM) tip characteristics. Magnetic contrasts obtained in MFM experiments are exploited to get the tip hysteresis loop in the influence of the dot and coercivity, remnant magnetization.

Two methods, a superhydride and a high temperature procedure, for the synthesis of [FePt](sub (100-x))Cr(sub x) nanoparticles with various Cr compositions and as-prepared particles sizes are reported. Cr is used as the means to tune the ordering temperature as a function of the size effect in FePt nanoparticles.

SmCo(sub 7-x)Cr(sub x) magnets are synthesized by mechanical alloying and subsequent annealing. The magnetization reversal process of the alloys is discussed according to the measurement of initial magnetization curves and minor hysteresis loops.

A Cr underlayer was doped with 10 at. % Ru to enlarge the Cr lattice and promote the Co(11.0) formation of the CoCrPtTaB magnetic layer by in-plane tensile stress at a recording layer/underlayer interface. The texture, grain size and magnetic characteristics of CoCrPtTaB/Cr(Ru) were examined as well. The CrRu(002) underlayer exhibit markedly enhanced Co(11.0) orientation, increasing coercivity and preferential alignment of the c-axis. The grain size and grain size distribution of the recording layer decreased as the CoCrPtTaB magnetic layer grew epitaxially on the CrRu underlayer. The grain size of the recording layer was reduced from 11.2 nm with a pure Cr underlayer to 5.4 nm with a CrRu underlayer. The latter is the smallest grain size yet reported for CoCr-based alloy recording media. Index Terms--Chromium alloys, cobalt alloys, epitaxial growth, magnetic recording.

A Ru-SiO2 intermediate layer is introduced between Ru and recording layers to reduce the intermediate layer thickness of CoCrPt-SiO2 perpendicular recording media. A structural analysis revealed that the Ru-SiO2 intermediate layer enhanced the oxide segregation in the initial growth region of the recording layer.

An experimental study of the magnetic phase diagrams of Cr-Al alloys doped with V and Mn to respectively decrease and increase the electron concentration per atom is reported. The magnetic phase transition temperature of three Cr-Al alloys are discussed in terms of changes in the nesting parameter of the electron and hole Fermi surface sheets.

The optical and magneto-optical properties of bulk [L2.sub.1] ordered [Co.sub.2]CrGa Heusler alloy (HA) are examined below and above the Curie temperature and are explained in terms of the band structure. The studies have shown that unlike bulk [L2.sub.1]-type ordered [Co.sub.2]CrGa HA sample, B2 structure order of [Co.sub.2]CrGa HA films have displayed negative temperature coefficient of resistivity.

The analysis of Cr-Mn alloy films that are epitaxially stabilized on GaSb (100) by suing molecular beam epitaxy is described. The structural and magnetic phase diagrams of the epitaxial Cr-Mn alloy films are presented.

Several x-ray diffraction and magnetization measurements are conducted to explain the different structural, as well as the magnetization properties of the [Tm.sub.2][Fe.sub.17-x][Cr.sub.x] compounds. An increase in the Cr content is shown to lead to a significant reduction in the saturation magnetization of the compounds.

A combination of the ferromagnetic resonance and vibrating sample magnetometer techniques is employed to explain the magnetic properties of the ultrathin Py/Cr/Py trilayers. The exchange coupling taking place between the ferromagnetic layers is shown to be highly dependent on the spacer layer thickness.

A bit patterned media fabrication method is described based on low energy nitrogen ion implantation. Nitrogen ion implantation of fcc-Co/Pd multilayer or hcp-CoCrPt single layer has suppressed their magnetizations at room temperature and writing and reading of the signal from individual dots are performed with a commercial perpendicular magnetic recording head.

Several studies are conducted to explain the properties, as well as the magnetic hysteresis behavior exhibited by the [Ru.sub.0.25][Cr.sub.0.75][O.sub.2] thin films. The intrinsic positive exchange bias observed in a single phase epitaxial thin film ferrimagnet is also analyzed.

Several studies are conducted to explain the various effects of phase transformation on the magnetic, as well as magnetocaloric properties of the first order phase transition materials. The realistic entropy behavior observed in these materials is also determined.

A combination of x-ray diffraction, magnetization and several other techniques is employed to explain the preparation, structure and the magnetic properties of the various ferrimagnetic Fe[Cr.sub.2-x][M.sub.x][S.sub.4] (M = In,Al) compounds. An increase in the Al and In concentrations is shown to lead to a sharp increase in their lattice constants.

The article discusses the synthesis, properties and applications of the various Fe-Co-Cr nanocomposites that are shown to exhibit low Curie temperatures and moderate magnetic moments. The compounds are shown to be widely used for self-regulated rf heating employed in polymer curing.

The article discusses a newly devised methodology, which can be used for the reduction of the artifact of metallic implant in the magnetic resonance imaging process. The optimal thicknesses of the paramagnetic coating of the different models are also determined.

Several studies are conducted to examine the long range exchange coupling taking place in the zinc-blende CrTe/ZnTe/MnTe trilayer. The shifts exhibited by the magnetic hysteresis loops of the compounds are also analyzed.

The low temperature molecular beam epitaxy technique is employed to explain the antiferromgnetic thickness dependence of the CrTe- MnTe exchange-bias system. The coercivity and the exchange bias field of the system are shown to be completely dependent on the thickness.

Several studies are conducted to explain the spin-polarized transport taking place in the Fe/Cr/MgO/Fe magnetic tunnel junctions. The presence of Cr layer is shown to lead to a sharp decrease in the tunnel magnetoresistance of the junctions.

The various effects of the Fe-based alloys on the modification of the [[delta].sub.1] and [[delta].sub.5] electron states for magnetic tunnel junctions are determined. The nature of the alloy metal is shown to have a significant impact on these states.

The detailed Raman spectra as well as magnetic and dielectric properties of chemically synthesized GdCr[O.sub.3] nanoparticles of size ranging from 40 to 60 nm is reported. The small dielectric loss value observed in GdCr[O.sub.3] nanoparticles which showed an interesting frequency dependent anomaly at lower temperature might be attributed to the coupling between magnetic and dielectric order parameters.

Several susceptibility and magnetization measurements are conducted to explain the critical behavior of the spinal compound, Cd[Cr.sub.2][S.sub.4]. The ferromagnetism of the compound is shown to be highly affected by the presence of correlated magnetic polarons in the system.

Polarized small-angle neutron scattering is used for measuring the local magnetic structure of writable thin-film perpendicular media with a granular CoCrPt-Si[O.sub.x] recording layer. The analytical and numerical approach based on transmission electron microscopy measurements of the grains have shown that the recording layer has fermomagnetically ordered core regions that are smaller in extent than the corresponding grains and have allowed a direct comparison of these two length scales.

30 keV [Kr.sup.+] ions are irradiated onto [L1.sub.2] ordered Cr[Pt.sub.3] alloy films prepared by a magnetron sputtering deposition followed by an appropriate heat treatment and the modification of the structure and magnetic properties of the Cr[Pt.sub.3] films are examined. The [L1.sub.2] Cr[Pt.sub.3] onto a fused quartz substrate has displayed a large perpendicular anisotropy due to the large lattice distortion.

A study was conducted to examine the magnetic coupling at interface of Co and Cr using ultrathin Co film on [Cr.sub.2][O.sub.3](0001) film. Findings revealed the exchange bias effect on coupling direction of Co and Cr.

The article studies the dependences of the structural, thermodynamic, elastic, and magnetic properties of [Cr.sub.2]GeC on pressure and temperature using quasiharmonic Debye model. Results suggest that the antiferromagnetic state is the ground state of [Cr.sub.2]GeC.

The magnetic and electrical properties of [Cr.sup.3+] substituted nickel ferrite prepared by wet chemical route are analyzed. The variation in resistivity is explained by Verwey hopping mechanism and the activation energy derived from the temperature variation in resistivity has increased with increasing concentration of [Cr.sup.3+] ions.

An RF sputtering technique is used to deposit Ti(5 nm)/CoCrPt(5-20 nm) bilayers with perpendicular magnetic anisotropy onto porous alumina films to form antidot arrays with period 105 nm and pore diameters ranging from 18 to 56 nm. The results obtained for the coercivities, domain size, and the magnetic behavior of the antidot arrays are also discussed.

The first-principles study is used for analyzing the magnetic and half-metallic properties of ordered Ca-Cr-As alloy with zinc-blende like structure. The results have shown that the compounds are half-metallic with magnetic moment determined by the Ca concentration and [Ca.sub.0.75][Cr.sub.0.25]As is a half-metallic antiferromagnet with no net magnetization.

The electronic structure of the films of [V.sub.1-x][Cr.sub.x][O.sub.2] is calculated by using density functional theory in the generalized gradient approximation and density functional theory with empirical on-site Coulomb correlations. The studies have shown that the ground state of rutile phase [V.sub.1-x][Cr.sub.x][O.sub.2] is quite simple and that V[O.sub.2] is paramagnetic and metallic for temperatures above 340 K where it is stable.