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Critical behavior of two-dimensional spin systems under the random-bond six-state clock model J. Appl. Phys. 112, 063924 (2012) Effect of spin drift on spin accumulation voltages in highly doped silicon Appl. Phys. Lett. 101, 122413 (2012) Spin-wave excitations induced by spin current through a magnetic point contact with a confined domain wall Appl. Phys. Lett. 101, 092405 (2012) Spin-torque effect on spin wave modes in magnetic nanowires Appl. Phys. Lett. 101, 072409 (2012) The influence of in-plane ferroelectric crystal orientation on electrical modulation of magnetic properties in Co60Fe20B20/SiO2/(011) xPb(Mg1/3Nb2/3)O3-(1−x)PbTiO3 heterostructuresIn this study, we start with the Landau-Lifshitz-Gilbert equation to describe the spinwaves in magnetic medium using the linearization approach. First, the reflection and refraction behaviors of spinwaves on an interface of a nonuniform magnetic medium is investigated. The study is then extended to spinwave propagation in lossless planar magnonic waveguides. Spinwave modes have been characterized based on the magnetic properties of the waveguides. Coupling between spinwaves in the structure of double magnonic waveguides is found to be possible due to the dipole interaction of the spinwaves. The spinwave coupling and power transfer associated with it is totally dependent on the waveguide structure and properties and the spinwave modes.

Spinwave propagation in clad cylindrical magnonic waveguides is investigated under linear approximation. With the assumption of no magnetic damping, characteristic equation to determine the bound spinwave modes has been obtained based on the structural and magnetic properties of the waveguides. The study is then applied to homogenous magnetic nanowires with no cladding. Spinwave characteristics and properties, such as the dispersion relationship and group velocity, can be described analytically.

In this paper we report on magnetization reversal processes of pinned layers in different ferromagnetic and anti-ferromagnetic bilayer and spin-valve structures by observing hysteresis, switching field distribution (SFD), and time-dependent effects. The fact that time-dependent coercivity Hc tendency is more pronounced in ordered AF materials than that of disordered AF materials implies a spin reversal of some AF grains with locally low pinning field and low blocking temperature. We propose a simple qualitative model to explain our results in terms of a distribution of the pinning reversal field and temperature in AF layer, which may be due to a grain size distribution in the AF layer and an incomplete and inhomogeneous phase transformation in some ordered AF materials. High resolution electron microscopy (HREM) results reveal that lattice spacing does change from place to place in AF region of some ordered AF materials. The evidence indicates an incomplete and inhomogeneous phase transformation in the ordered AF systems, supporting the results of the magnetization reversal process study.

In this study, we predict crystalline ordering of magnetic nanoparticles in a bilayer structure where only magnetic dipole interaction is taken into account. Estimates show that the two-dimensional lattice structure can be observed in the liquid nitrogen temperature regime. The results can be extended to magnetic nanoparticle multilayers. In addition, the study implies an order–disorder phase transition of the magnetic nanoparticle ensemble induced by external perpendicular magnetic fields.