Author: Jae-Young YiPublisher:
ISBN:
Category : Anisotropy
Languages : en
Pages : 414
Book Description
Microstructure and Magnetic Properties of Co-(CoO, CoNiO̳2, NiO) and CoxN̳i̳1̳-x̳-CoO Nanocomposite Thin Films
Author: Jae-Young YiPublisher:
ISBN:
Category : Anisotropy
Languages : en
Pages : 414
Book Description
Microstructure and Magnetic Properties of Co-CoO Nanocomposite Films
Author: Jae Y. YiPublisher:
ISBN:
Category :
Languages : en
Pages : 6
Book Description
The effect of exchange anisotropy on nanosize Co particles was studied in Co-CoO nanocomposite thin films for possible applications for magnetic storage media. XRD analyses showed nanosize hcp Co particles and (111) textured CoO phase. A broken columnar structure was observed in cross-section TEM images. Very large room temperature coercivity (^ 1 kOe) was observed and believed to be doe to a shape effect and possible local exchange coupling. Large exchange anisotropy at low temperatures and linear type temperature dependence were explained by finite size effects and thermal relaxation of the CoO particles. A slow decrease of thermoremanent moment (TRM) with temperature and large TRM at room temperature indicated that the exchange anisotropy significantly modified the anisotropy energy barrier of the Co crystallites in the CoO matrix. The results indicated that the exchange anisotropy could be used to stabilize nanosize ferromagnetic particles.
Magnetic Properties and Microstructures of Ni80Fe20/CoxNi1-xO Exchange Coupled Thin Films
Author: Wei CaoDissertation Abstracts International
Author: Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 850
Book Description
Microstructure and Magnetic Properties of Cobalt-based Thin Films for Magnetic Recording
Author: Li TangStructure, Microstructure and Magnetic Properties of Electrodeposited Co and Co-Pt in Different Nanoscale Geometries
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Thin films and nanowires of Co-Pt have been prepared by means of electrodeposition. Composition, structure, microstructure and magnetic properties have been intensively studied using X-ray diffraction, scanning electron microscopy and vibrating sample magnetometry and correlated to the deposition parameters such as electrolyte composition, deposition current and/or potential. Co rich Co-Pt films have been deposited at various current densities. A nearly constant composition of Co70Pt30 was achieved for current densities between 18 and 32 mA/cm2. Detailed texture measurements confirmed an increasing fraction of the hexagonal phase with its c-axis aligned perpendicular to the film plane with increasing current density. Accordingly, magnetic properties are strongly affected by the magnetocrystalline anisotropy of the hexagonal phase that competes with the shape anisotropy of the thin film geometry. Co-Pt nanowires have been prepared within alumina templates at different deposition potentials between -0.6 and -0.9VSCE changing the composition from nearly pure Pt to Co. The composition Co80Pt20 was observed at a deposition potential of -0.7VSCE. Co-Pt nanowires are nanocrystalline in the as-deposited state. Magnetic measurements reveal changing fcc and hcp phase fractions within the wires as the effective anisotropy significantly differs from the expected shape anisotropy for nanowires with high aspect ratio. This change in effective anisotropy is attributed to the preferential alignment of the c-axis of hcp Co-Pt phase perpendicular to the nanowires axis. A promising alternative with much smaller feature sizes is the diblock copolymer template. Electrodeposition of Co and Co-Pt into these templates has been carried out. Inhomogeneities in the template thickness as well as a certain substrate roughness have been identified to be the reasons for inhomogeneous template filling. Thus magnetic properties are dominated by large deposits found on top of the template. Additiona.
A Study of Magnetic Properties and Microstructure of Sputtered Co-Cr Thin Films
Author: Yōichi UchiyamaMagnetic Properties of Nanocomposite Cobalt-based Thin Films
Author: J. Mark MeldrimMagnetic properties and microstructure of ion implanted thin cobalt films
Author: Andrew Collin CampbellPublisher:
ISBN:
Category : Thin films
Languages : en
Pages : 142
Book Description
Structural and Magnetic Properties of Co/Pt and Related Multilayer Thin Films
Author: Gerardo Antonio BerteroPublisher:
ISBN:
Category :
Languages : en
Pages : 352
Book Description