Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Photoemission And Electronic Structure Of Tungsten-Based Metallic Glasses And Alloys , M.A. Engelhardt, Sitaram Jaswal, David J. Sellmyer
Photoemission And Electronic Structure Of Tungsten-Based Metallic Glasses And Alloys , M.A. Engelhardt, Sitaram Jaswal, David J. Sellmyer
David Sellmyer Publications
The structure and electronic density of states of intertransition-metal glasses of the form TxW1-x have been investigated, where T=Cu, Ni, and Co. The film samples were prepared by cosputtering in a chamber with a rapidly rotating, water-cooled substrate. Experiments included x-ray diffraction and ultraviolet photoemission at photon energies of 21.2 and 40.8 eV, and electronic-structure calculations were performed with a self-consistent linear combination of muffin-tin-orbitals method. For the calculations the structures were simulated by either disordered crystalline or amorphous clusters of 60–64 atoms in a periodically extended supercell. The range of amorphous alloy formation was determined …
Magnetic And Structural Properties Of Co/Cr Multilayers With In-Plane Anisotropy, D. Wang, David J. Sellmyer
Magnetic And Structural Properties Of Co/Cr Multilayers With In-Plane Anisotropy, D. Wang, David J. Sellmyer
David Sellmyer Publications
Previously we studied the effect of Cr spacer layer on in-plane coercivity in Co/Cr multilayered films. It was found that the high coercivity is related to the easy axis in-plane orientation and the character of the composition modulation. In this paper, the dependence of the saturation magnetization as a function of Co layer thickness is used to study the interface structure. The layer structure is confirmed by small angle x-ray diffractometry for typical films. The magnetic interaction among the grains is studied by examining deviation from the behavior predicted by the Wohlfarth model for noninteracting single-domain particles. Journal of Applied …
Temperature And Thickness Dependence Of Coercivity And Magnetization Of Co/Cu And Co/Si Multilayers, S. Nafis, John A. Woollam, Z.S. Shan, David J. Sellmyer
Temperature And Thickness Dependence Of Coercivity And Magnetization Of Co/Cu And Co/Si Multilayers, S. Nafis, John A. Woollam, Z.S. Shan, David J. Sellmyer
David Sellmyer Publications
Co/Cu and Co/Si multilayers of total thickness ~3000 Å were prepared by rf and dc magnetron sputtering. The nominal thicknesses of the individual layers were in the range of 4 to 100 Å. A large coercivity (Hc) at 10 K was observed for very thin layers of Co in Co/Cu samples, and it decreased with increase of the Co layer thickness. For very thin layers of Co in Co/Cu samples, the layer behaved superparamagnetically. Similar behavior was not to be observed in Co/Si samples. With increased substrate temperature (Ts) during deposition, Hc was …
Electronic And Magnetic Structures Of The Rare-Earth Compounds R2Fe17NΞ, Sitaram Jaswal, W.B. Yelon, George C. Hadjipanayis, Y.Z. Wang, David J. Sellmyer
Electronic And Magnetic Structures Of The Rare-Earth Compounds R2Fe17NΞ, Sitaram Jaswal, W.B. Yelon, George C. Hadjipanayis, Y.Z. Wang, David J. Sellmyer
David Sellmyer Publications
Structural and magnetic properties of the rare-earth compounds R2Fe17Nξ have been studied with neutron-diffraction measurements and self-consistent spin-polarized electronic-structure calculations. The diffraction results indicate for the Nd compound that N goes into two sites in two or more phases of varying fractional N occupations. For the Y compound N occupies only one site. Electronic-structure calculations for Y2Fe17 and Y2Fe17N3 give excellent results for site-dependent Fe moments, and, with spin-fluctuation theory, explain the large change in the Curie temperature on nitrogenation.
Effect Of Microstructure On Coercivity Of C-Axis In-Plane-Oriented Co/Cr Multilayered Films, D. Wang, David J. Sellmyer, George C. Hadjipanayis
Effect Of Microstructure On Coercivity Of C-Axis In-Plane-Oriented Co/Cr Multilayered Films, D. Wang, David J. Sellmyer, George C. Hadjipanayis
David Sellmyer Publications
The effect of the insertion of nonmagnetic Cr planes on coercivities of thin Co films has been studied in Co/Cr multilayered films. The in-plane coercivity Hc║ can be as high as 1800 Oe and can be adjusted easily, ranging from 650 to 1800 Oe. The large Hc║ is related to the Co(110) in-plane orientation which is induced by a Cr(100) in-plane-oriented underlayer. In addition, it appears that a decreasing saturation magnetization Ms, a decreasing average structural coherence length D in the direction perpendicular to the film, and a narrowing distribution of D are correlated …
Magneto-Optic And Optical Characterization Of Tb/Co Compositionally Modulated Amorphous Films, Liang-Yao Chen, Ping He, S. Nafis, William A. Mcgahan, John A. Woollam, David J. Sellmyer
Magneto-Optic And Optical Characterization Of Tb/Co Compositionally Modulated Amorphous Films, Liang-Yao Chen, Ping He, S. Nafis, William A. Mcgahan, John A. Woollam, David J. Sellmyer
David Sellmyer Publications
Amorphous Tb/Co compositionally modulated films were deposited on Si substrates with different modulation layer thicknesses ranging from about 2.5 to 15 Å. The nominal Tb to Co layer thickness ratios were systematically varied and the complex refractive index (n and k) and polar magneto-optical Kerr effects (rotation and ellipticity) were measured in the 3000–8000-Å spectral range as well. The samples were divided into two groups. In one group, the thickness of the Co layers was fixed, the Tb layer thickness varied. In the second group, the thickness of the Tb layer was fixed, and that of the Co …