Spin torque from spin current applied to a nanoscale region of a ferromagnet can act as negative magnetic damping and thereby excite self-oscillations of its magnetization. In contrast, spin torque uniformly applied to the magnetization of an extended ferromagnetic film does not generate self-oscillatory magnetic dynamics but leads to reduction of the saturation magnetization. Here we report st...

High-precision dc magnetization measurements have been made on Cu(C4H4N2) (NO3)2 in magnetic fields up to 14.7 T, slightly above the saturation field Hs=13.97  T, in the temperature range from 0.08 to 15 K. The magnetization curve and differential susceptibility at the lowest temperature show excellent agreement with exact theoretical results for the spin-1/2 Heisenberg antiferromagnet in one d...

Metal-insulator granular film is technologically important for microwave applications. It has been challenging to obtain simultaneous high electrical resistivity and large saturation magnetization due to the balance of insulating non-magnetic and metallic magnetic components. FeAlO granular films satisfying both requirements have been prepared by pulsed laser deposition. The as-deposited film e...

Yttrium iron garnet powders have been synthesized by chemical coprecipitation using two different precursors, nitrates and chlorides, and by an oxides mixture route. It is shown that depending on the precursors and synthesis conditions used pure yttrium iron garnet powders can be obtained with a mono or multidomain magnetic behaviour. The yttrium iron garnet crystalline structure, as studied by...

The paper reviews recent experimental results concerning a wide variety of magnetic nanofluids with high saturation magnetization. Magnetic, rheological and magneto-rheological properties are presented and discussed, especially related to nanostructural processes and colloidal stability in applied magnetic field.

magnetic nanoparticles are the good choice for using in mri as the contrast agent. iron oxide particles such as magnetite (fe3o4) or its oxidized form maghemite (γ-fe2o3) are the most commonly employed in biomedical applications. in this study, we synthesized and optimized the preparation of chitosan manganese-ferrite nanoparticles (cmn-fe nps) and evaluated its ability for the mice macrophage ...

Amide proton transfer (APT) imaging has shown promise as an indicator of tissue pH and as a marker for brain tumors. Sources of error in APT measurements include direct water saturation, and magnetization transfer (MT) from membranes and macromolecules. These are typically suppressed by postprocessing asymmetry analysis. However, this approach is strongly dependent on B(0) homogeneity and can i...

cobalt ferrite is an important magnetic material due to their large magneto-crystalline anisotropy, high cohercivity, moderate saturation magnetization and chemical stability.in this study, cobalt ferrites nanoparticles have been synthesized by the co-precipitation method and a new microemulsion route. we examined the cation occupancy in the spinel structure based on the “rietveld with energies...

We investigate the ground state of a uniaxial ferromagnetic plate with perpendicular easy axis and subject to an applied magnetic field normal to the plate. Our interest is the asymptotic behavior of the energy in macroscopically large samples near the saturation field. We establish the scaling of the critical value of the applied field strength below saturation at which the ground state change...

the synthesis of nano- structured cobalt through a controlled chemical process followed by heat treating at various temperatures is studied. the product is characterized by icp, xrd, fesem , and tem, indicating that the as- synthesized particles have an amorphous structure with 1.76 for co/b ratio, an average size of 50 nm. the transformation of intermediate phases into single phase nano- cryst...