We conducted a thorough experimental and numerical study of the micromagnetic properties Permalloy (Ni$_{80}$Fe$_{20}$) microdisks exhibiting target domain structures at remanence. Vortex configurations are quite common in such correspond to an in-plane flux closure configuration cylindrical symmetry with out-of-plane magnetized core. In contrast, observed thicker characterized by vortex compon...

Existing techniques for characterization of longitudinal recording media using remanence measurements are extended to perpendicular media, in particular to Alumite, and correction for demagnetizing fields is taken into account. It is found that these techniques have limited value because of the sensitivity of the analysis to the correction factor used. Measurement of the recoil lines is investi...

Microstructural effects on the magnetic behavior of rf-sputtered CoFe–AgCu granular alloys are examined through the study of the in-plane remanence-to-saturation magnetization ratio, M r /M s , as a function of temperature, ferromagnetic volume content, xv , and annealing temperature. At low ferromagnetic contents (xv<0.25), the M rM s ratio in as-deposited samples tends towards 0.5 at low temp...

Colloidal Fe3O4 nanoparticles were synthesized using a gamma-radiolysis method in an aqueous solution containing iron chloride in presence of polyvinyl alcohol and isopropanol as colloidal stabilizer and hydroxyl radical scavenger, respectively. Gamma irradiation was carried out in a 60Co gamma source chamber at different absorbed doses. Increasing the radiation dose above a certain critical do...