This paper reports on the magnetic properties of magnetosomes in the freshwater magnetotactic bacterium Aquaspirillum nlllgnetOlaClicwn. The magnetosomes are well crystallized particles of magnetite with dimensions of 40 to 50 nm, which are arranged within cells in a single linear chain and are within the single-magnetic-domain (SO) size range for. magnetite. A variety of magnetic properties ha...

The equations of magnetohydrostatic equilibria for a plasma in a gravitational field are investigated analytically. For equilibria with one ignorable spatial coordinate, these equations reduce to a single nonlinear elliptic equation for the magnetic vector potential A. This equation depends on an arbitrary function of A that must be specified. In this paper analytical nonlinear periodic solutio...

We present numerical 2D magnetostatic models for sunspot penumbrae consisting of radially aligned field-free gaps in a potential magnetic field, as proposed by Spruit and Scharmer (2006). The shape of the gaps and the field configurations around them are computed consistently from the condition of magnetostatic pressure balance between the gap and the magnetic field. The results show that field...

We develop an effective low-frequency theory of the electromagnetic field in equilibrium with thermal objects. The aim is to compute thermal magnetic noise spectra close to metallic microstructures. We focus on the limit where the material response is characterized by the electric conductivity. At the boundary between empty space and metallic microstructures, a large jump occurs in the dielectr...

Magnetic skyrmions are promising information carriers for dense and energy-efficient storage owing to their small size, low driving-current density, topological stability. Electrical detection of is a crucial requirement drive skyrmion devices toward applications. The use magnetic tunnel junction (MTJ) commonly suggested this purpose as MTJs key spintronic large-scale commercialization that can...

Hematite carries magnetic signals of interest in tectonic, paleoclimatic, paleomagnetic, and planetary studies. First-order reversal curve (FORC) diagrams have become an important tool for assessing the domain state of, magnetostatic interactions among, particles such We present here FORC diverse hematite samples, which provide a catalog comparison with other studies explain key features observ...

Magnetic coercivity is often viewed to be lower in alloys with negligible (or zero) values of the anisotropy constant. However, this explains little about dramatic drop FeNi at a non-zero value. Here, we develop theoretical and computational tool investigate fundamental interplay between material constants that govern bulk magnetic alloys. The two distinguishing features our are that: (a) intro...

Abstract Full control of magnetic properties in exchange coupled systems requires a good understanding 3D configuration with lateral and in-depth resolution. Here we show results from soft X-ray tomographic reconstruction which allow determining, solely the experimental data, detailed description vector ferrimagnetic Gd 12 Co 88 /Nd 17 83 /Gd 24 76 trilayer engineered competing anisotropy, magn...