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Simulations of mechanical or comfort properties of fibers, yarns and textile fabrics have been developed for a long time. In the course of increasing interest in smart textiles, models for conductive fabrics have also been developed. The magnetic properties of fibers or magnetic coatings, however, are almost exclusively being examined experimentally. This article thus describes different possibilities of micromagnetically modeling magnetic fibers or coatings. It gives an overview of calculation times for different dimensions of magnetic materials, indicating the limits due to available computer performance and shows the influence of these dimensions on the simulated magnetic properties for magnetic coatings on fibers and fabrics.

We study the Imbert–Fedorov (IF) shifts of a reflected Gaussian beam from anisotropic topological insulators (TIs). Aiming, respectively, at the two types of TI surface perturbations that can alter the surface optical properties, i.e., a magnetic coating and an applied magnetic field, we discuss the dependences of the IF shifts on the axion field, the TI's extent of anisotropy, the angle of incidence and the applied magnetic field. For a left-elliptically polarized incident beam, a positive (negative) axion field can lead to the decrease (increase) of the IF shifts relative to a conventional insulator in the magnetic coating case, and in the applied magnetic field case, the crossover of the IF shifts between the positive and the negative values can be realized by adjusting some external parameters. Also, the properties of the IF shifts are discussed for linearly and circularly-polarized incident beams. The results show that TI might be a desirable candidate for controlling flexibly the IF shifts.

We investigate the importance of using nanotips on a point contact spin-transfer torque (STT) experiment. A systematic analysis comparing the STT in a magnetic thin film in current-perpendicular-to-plane (CPP) geometry sample for magnetic coated and uncoated tungsten nanotips is shown. The STT effect presents a reverse resistance to current behavior when using a magnetic coating layer on the nanotips. We demonstrate that the magnetic layer on the tip may assume the role of a polarizer layer. This effect opens up the possibility of exploiting simpler architectures in STT-based devices, such as STT-random access memory (STT-RAM).

In order to improve the spatial resolution achieved by magnetic force microscopy (MFM) technique and its derivatives, we employ here advanced MFM tips fabricated by means of focused ion beam (FIB) milling. The magnetic coating applied on these tips is a CoCr film of 10 nm thickness. The MFM measurements on hard disk test samples reveal the achieved high resolution, and the measurement on a garnet film demonstrates the low invasiveness. High-frequency MFM (HF-MFM) is a development of the MFM technique to observe the HF stray fields emerging from magnetic recording writer poles at their operating conditions. By means of HF-MFM, magnetic recording writer poles are characterized in the frequency range 100–1,000 MHz. Up to now, all HF-MFM experiments conducted were using standard MFM cantilevers. From the HF-MFM images obtained using the advanced MFM cantilevers, it is clearly seen that the spatial resolution is considerably improved over the images obtained using standard MFM tips. However, the 10 nm thick magnetic coating of the cantilevers is found to work properly only at frequencies of up to about 500 MHz. SCANNING 30: 27–34, 2008. © 2008 Wiley Periodicals, Inc.

A high-frequency magnetic force microscope (HF-MFM) is built up for the observation of the high-frequency stray fields of harddisk write heads. We demonstrate the performance of the system using harddisk write heads from different manufacturers. We show that the use of advanced high-aspect ratio MFM cantilevers yields HF-MFM images with clearly improved spatial resolution. Furthermore, we present results obtained using MFM cantilevers with a magnetic coating of Ba3Co2Fe24O41 (BCFO).

In this chapter Magnetic Force Microscopy is treated in detail. The emphasis is on high resolution and the design and realisation of MFM tips.

The magnetic characterization of four experimental advanced double-coated MP tapes with different magnetic coating thickness has been completed. Although standard vibrating sample magnetometer (VSM) measurements show very similar characteristics such as coercivity, squareness and orientation ratio (OR), alternative measurements show distinct differences in addition to their magnetic thickness. The in-plane distribution of easy axes (EAD) measured using a bi-axial VSM, show that the distribution width increased as the magnetic coating thickness decreased. A theoretical relation between OR and EAD was used to determine the out-of-plane distribution width. This was found to be narrower than the in-plane equivalent, as expected. The out-of-plane distribution width decreased as the magnetic thickness decreases, contrary to the in-plane variation.

The structure of magnetic coating films was analyzed by the ultra-small-angle X-ray scattering (USAXS) technique. Small-angle X-ray scattering (SAXS) has been used to investigate the size, shape, and correlation of the nm sized structure. USAXS, with a measurable range extending to the µm order, can be used to analyze the submicron sized structure of paints and coating films. Preliminary USAXS experiments for a magnetic paint and magnetic coating films revealed that USAXS is useful to evaluate the structure of the particles in the paint and the films. Combined with other experimental methods, USAXS will provide a new kind of information about the structural analysis.

To experimentally investigate the acoustical behavior of different dual-mode nanosized contrast agents (NPCAs) for echographic medical imaging at low ultrasound (US) frequency.We synthesized three different nanosized structures: (1) Pure silica nanospheres (SiNSs); (2) FePt-iron oxide (FePt-IO)-coated SiNSs; and (3) IO-coated SiNSs, employing three different diameter of SiNS-core (160, 330 and 660 nm). Tissue mimicking phantoms made of agarose gel solution containing 5 mg of different NPCAs in 2 mL-Eppendorf tubes, were insonified by a commercial echographic system at three different low US pulse values (2.5, 3.5 and 4.5 MHz). The raw radiofrequency signal, backscattered from each considered NPCA containing sample, has been processed in order to calculate the US average backscatter intensity and compare the acoustic behavior of the different NPCA types.The highest US contrast was exhibited by pure SiNSs; FePt-IO-coated SiNSs acoustical behavior followed a similar trend of pure SiNSs with a slight difference in terms of brightness values. The acoustic response of the examined NPCAs resulted function of both SiNS diameter and US frequency. Specifically, higher US frequencies determined higher value of the backscatter for a given SiNS diameter. Frequency-dependent enhancement was marked for pure SiNSs and became less remarkable for FePt-IO-coated SiNSs, whereas IO-coated SiNSs resulted almost unaffected by such frequency variations. Pure and FePt-IO-coated SiNSs evidenced an image backscatter increasing with the diameter up to 330 nm. Conversely, among the types of NPCA tested, IO-coated SiNSs showed the lowest acoustical response for each synthesized diameter and employed US frequency, although a diameter-dependent raising trend was evidenced.The US characterization of magnetically covered SiNS shows that FePt-IO, rather than IO, was the best magnetic coating for realizing NPCAs suitable for dual mode imaging of deep organs, combining US and magnetic resonance imaging.

While the properties of conductive fibres and coatings on textiles can easily be measured and calculated, magnetic coatings of fibres, yarns and fabrics still lack descriptions of their physical properties. Since magnetic textiles can be used for a variety of applications, from magnetic filters to invisible water-marks to magnetic coils and sensors, simulations would be supportive to understand and utilize their properties. The article gives an overview of different coatings on textile fibres, varying the magnetic materials as well as the fibre composition, giving rise to the interactions between neighbouring coated fibres. In this way, it is possible to understand the strong shape anisotropy which must be taken into account when the magnetic properties of textiles are to be tailored. Additionally, the differences between several possible magnetic coating materials become visible. This study can help adjusting the magnetic properties of textile fabrics to a desired application.

CrO2 particles provide a good basis for proper pulse recording due to their high output at short wavelengths, combined with low noise print-through. Furthermore, one outstanding features is their low electrical resistance. It avoids statics charging of the magnetic coating and thus eliminates both dropouts caused by the attraction of loose particles and tape edge damage cause by a rough tape pack due to tape static.

This paper describes two optical devices: one device is capable of measuring real-time the surface roughness of the magnetic coating in the production process in the range of 5 to 40 nm (RMS) and the other device is designed for table measurements. Both devices are easy-to-install and easy-to-use.

This paper discusses the important innovations in disk file manufacturing at IBM over the past twenty-five years. Technology advances in the key components of disk files- the magnetic read/write head, its air bearing support, and the disk substrate and magnetic coating- have permitted almost four orders of magnitude increase in areal recording density since the first disk file, the IBM 350, was shipped in 1957. Manufacturing capability for these basic recording technology components has been the key to realizing the cost/performance promise of each new technology. The evolution of this manufacturing capability is discussed with an emphasis on important innovations in processes, materials, tools, and testing techniques.

This paper describes a magnetometer with a miniature transducer which can be scanned automatically. The active area of the transducer is 0.64×0.76 mm and its drive circuit is constructed from wire plated with a magnetic coating. The magnetometer is capable of detecting static magnetic fields as low as 0.02 Oe and can measure magnetic fields as close as 0.08−0.10 mm from a relatively flat surface since the transducer is flat and rugged. The magnetometer is simple to operate and has a fast response. The instrument has been applied to the measurements of magnetic fields arising from remanent magnetization in experimental plated‐wire memory planes and regions of magnetic activity in geological rock specimens.