For the study of the relationship between the domain wall motion (DWM) and the coercivity in the samples of Dy-free Nd-Fe-B sintered magnets, the DC susceptibility (χDC) in the initial magnetization from the thermally demagnetized state and the DWM in the partially demagnetized state after the full magnetization in 5T-pulse field were measured. In the high coercivity (μ0Hc) samples of μ0Hc=1.35...

As a tribute to the scientific work of Professor Gareth Thomas in the field of structure-property relationships this paper delineates a new possibility of Lorentz transmission electron microscopy (LTEM) to study the magnetic properties of soft magnetic films. We show that in contrast to the traditional point of view, not only does the direction of the magnetization vector in nano-crystalline fi...

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The spin transfer phenomenon provides a new method to manipulate magnetization without applying an external magnetic field and a new playground to study the spin degree of freedom of electrons. Two types of magnetic dynamics excited by the spin transfer torque from a direct current were predicted in 1996: magnetization reversal and steady-state precession. The physics of spin-torque-induced mag...

Magnetization dynamics in nanomagnets has attracted broad interest since it was predicted that a dc current flowing through a thin magnetic layer can create spin-wave excitations. These excitations are due to spin momentum transfer, a transfer of spin angular momentum between conduction electrons and the background magnetization, that enables new types of information processing. Here we show ho...

We propose a method for inducing magnetization reversal using an AC spin current polarized perpendicular to the equilibrium magnetization of the free magnetic layer. We show that the critical AC spin current is significantly smaller than the corresponding DC one. The effect is understood as a consequence of the underdamped nature of the spin-torque oscillators. It allows to use the kinetic iner...

We investigated the wall-motion and nucleation activation volumes of Co/Pt multilayer films prepared by dc magnetron sputtering under various Ar sputtering pressures. Delicate analysis of time-resolved domain evolution patterns reveals that the nucleation activation volume is generally smaller than the wall-motion activation volume in all the samples, which is consistent with the nucleation-dom...