The structures and magnetic properties of Pr–Fe–Al alloys produced by the metallic mold casting method were investigated. The Pr–Fe–Al alloy consisted of the amorphous phase together with the non-ferromagnetic Pr phase. Magnetic measurements confirmed that the origin of coercivity in the alloys was the amorphous phase. It was found that the Curie temperature and coercivity of the alloys were st...

The cooling field dependence of the exchange bias field in ferromagnet/antiferromagnet (FM/AF) multilayers demonstrates that the bulk AF spin structure plays a crucial role on the origin of exchange bias. FM/AF/FM trilayers were designed to eliminate any interlayer exchange coupling between the FM slabs. By choosing the magnetic cooling field, the AF is ordered below its Néel temperature with t...

Electrical control of magnetic properties is crucial for device applications in the field of spintronics. Although the magnetic coercivity or anisotropy has been successfully controlled electrically in metals as well as in semiconductors, the electrical control of Curie temperature has been realized only in semiconductors at low temperature. Here, we demonstrate the room-temperature electrical ...

We have studied the nucleation in the nearest neighbour ferromagnetic Ising model, in different (d) dimensions, by extensive Monte Carlo simulation using the heat-bath dynamics. The nucleation time (τ) has been studied as a function of the magnetic field (h) for various system sizes in different dimensions (d = 2, 3, 4). The logarithm of the nucleation time is found to be proportional to the po...

Fe(x)Pt(y)Au(100-x-y) nanoparticles of size 3.5 nm were prepared by polyol reduction of platinum acetylacetonate and gold acetate and the thermal decomposition of iron pentacarbonyl. The as-synthesized nanoparticles with disordered fcc structure were then heat treated to transform to the L1(0) structure with high magnetocrystalline anisotropy. By tuning the stoichiometry of the Fe(x)Pt(y)Au(100...

Thin 001 textured FePt and CoPt polycrystalline films (5 nm) were deposited with an MgO polycrystalline underlayer on an oxidized Si substrate followed by a Rapid Thermal Annealing (RTA) process. Structural analysis indicated the samples to be fully ordered after 10 minutes (min) of RTA at 700 C. The magnetic hysteresis exhibited strong perpendicular anisotropy and a coercivity ( ) between 6 an...

The emergence of exchange bias and coercivity enhancement has been investigated in epitaxial CoO/Fe films with varied antiferromagnet (AF) thicknesses, even smaller than the critical value where frozen CoO spins are detectable. Vector magnetometry first-order reversal curve (FORC) measurements reveal different thickness dependence enhancement, including evolution magnetization from a high coerc...

Using out-of-plane magnetized layers, a lateral shift register made from discrete elements is demonstrated. By carefully designing the in-plane shape of the elements which make up the shift register, both the position of nucleation of new domains and the coercivity of the element can be controlled. The dipole field from a neighboring element, placed tens of nanometers away, creates a bias field...

Pinning type coercivity has been induced in large sø50 mmd particles of Sm2Fe17N3 by irradiation with 5 GeV Pb561 ions. Mössbauer spectroscopy is used to analyze the structure of the defects and estimate their volume. Magnetization measurements indicate that the induced defects are anisotropic in shape. A model of strong pinning by cylindrical defects is employed to deduce a defect radius of or...