The phase velocity of light is co–parallel to the direction of energy flow in classical vacuum. However, in certain uncommon materials, these two vectors can be oppositely directed, in which case the phase velocity is termed ‘negative’. This negative phase velocity (NPV) gives rise to many exotic phenomenons, such as negative refraction, inverse Doppler shift and inverse C̆erenkov radiation, and...

We present particle dynamics simulations for the response of magnetorheological (MR) uids upon application of a magnetic eld. The particles motion is considered to be governed by magnetic, hydrodynamic and repulsive interactions. Fluid-particle interactions are accounted for via Stokes' drag while inter-particle repulsions are modeled through approximate hard-sphere rejections. In accordance wi...

Ordinal excitations of three-magnon decay, modulation instability and four-magnon decay processes of magnetostatic surface waves propagating in a pure yttrium iron garnet film are investigated in accordance with the relationship between the magnetostatic wave frequency and the internal magnetic field. Onset of the modulation instability is realized as a result of tnodification of n~agnetostatic...

We demonstrate the possibility of obtaining a rich set of self-assembled arrays from a single component cobalt nanocrystal (NC) system by a controlled variation of size, shape and inter-particle interactions. By selecting appropriate conditions in which one of a set of weak but competing interaction forces (steric, van der Waals, depletion, or magnetostatic) dominates we can reproducibly achiev...

High-quality densely packed hexagonal arrays of Ni nanowires have been prepared by filling self-ordered nanopores in alumina membranes. Nanowires with different diameter d ~18–83 nm! and lattice parameter D ~65 and 105 nm! have been studied by atomic force, high resolution scanning electron microscopies, Rutherford backscattering, and vibrating sample magnetometer techniques. Axial loops coerci...

Magnetoelectric coupling in multiferroic heterostructures can produce large lateral modulations of magnetic anisotropy enabling the imprinting of ferroelectric domains into ferromagnetic films. Exchange and magnetostatic interactions within ferromagnetic films oppose the formation of such domains. Using micromagnetic simulations and a one-dimensional model, we demonstrate that competing energie...

Abstract In this paper the magnetostatic energy in a ferromagnetic thin film with two imperfect, rough surfaces has been calculated. It has been shown that the surface roughness gives in some cases a considerable contribution to an effective perpendicular anisotropy. Within the model assumed it has been proved that the value of magnetostatic energy and, as a consequence, the anisotropy in a thi...

a simple new closed form of the green function for axisymmetric magnetostatic problemsis found analytically in cylindrical coordinates. the result is verified by applying several examples.

Well-defined nanoscale flux-closure polygons (nanogons) have been fabricated on hydrophilic surfaces from the face-to-face self-assembly of magnetite nanocubes. Uniform ferrimagnetic magnetite nanocubes (∼86 nm) were synthesized and characterized with a combination of electron microscopy, diffraction, and magnetization measurements. The nanocubes were subsequently cast onto hydrophilic substrat...