The dynamics of a random (quenched) field Ising model (in two dimension) at zero temperature in the presence of an additional sinusoidally oscillating homogeneous (in space) magnetic field has been studied by Monte Carlo simulation using the Metropolis single spin flip dynamics. The instantaneous magnetisation is found to be periodic with the same periodicity of the oscillating magnetic field. ...

Conventional MRI sequences do not permit the distinction between the different pathological characteristics (oedema, demyelination, gliosis, axonal loss) of the multiple sclerosis plaque. Magnetisation transfer imaging and transverse magnetisation decay curve (tMDC) analysis may be more specific. These techniques have been applied to the optic nerves in 20 patients with optic neuritis and the r...

The aperiodic T-A180Mn20 phase is magnetic with an effective moment 1.3 pg / Mn. Below 4.1 K a spin glass state is observed. The T-phase and the quasi-crystalline A173Mn21Si6 phase have similar magnetic properties. The crystalline phase, obtained by annealing the T-phase, is less magnetic than the T-phase. Quasi-crystalline (qc) phases, first discovered in Al-Mn based alloys, are aperiodic crys...

We show how tumour heating in magnetic hyperthermia can become more homogeneous through exploitation of magnetisation dynamics interacting particles.

for the time dependence of the macoscopic magnetisation M(t) of a sample under the influence of an external field H(t) where γ =μ / Ih is the gyromagnetic ratio of the nuclei under consideration with magnetic moment μ and spin I, i, j, and k are the usual triad of unit vectors along the Cartesian axes. The external field has the form H(t) = H0k + H1(t), where H0 is strong and constant while H1 ...

By Monte Carlo simulations in the canonical ensemble, we have studied the magnetic anisotropy in Fe/Dy amorphous multilayers. This work has been motivated by experimental results which show a clear correlation between the magnetic perpendicular anisotropy and the substrate temperature during elaboration of the samples. Our aim is to relate macroscopic magnetic properties of the multilayers to t...

M. Symms, P. Boulby, G. Barker Institute of Neurology, London, United Kingdom, Institute of Psychiatry, London, United Kingdom Synopsis A technique to validate cross-modality registration techniques is described. Serial scans are used from an interleaved MTR measurement sequence that acquires intrinsically registered images with proton density and Magnetisation Transfer weighting. The registrat...

Off-axis electron holography in the transmission electron microscope is used to record magnetic induction maps of closely spaced magnetite crystals in magnetotactic bacteria at room temperature and after cooling the sample using liquid nitrogen. The magnetic microstructure is related to the morphology and crystallography of the particles, and to interparticle interactions. At room temperature, ...