A Study on an Easy-Plane FeSi Composite with High Permeability and Ultra-Low Loss at the MHz Frequency Band.

An easy-plane FeSi composite with excellent magnetic properties and loss properties at MHz were proposed. The easy-plane FeSi composite has ultra-low loss at 10 MHz and 4 mT, about 372.88 kW/m.

Genetic Algorithms to Automate the Design of Metasurfaces for Absorption Bandwidth Broadening.

In this paper, we present a method to automate the design of an efficient metasurface, which widens the bandwidth of the substrate. This strategy maximizes the potential of the substrate for the application of broad-band absorption. The design is achieved by utilizing the coding metasurface and a combination of two types of intelligent algorithms.

Micromagnetic Configuration of Variable Nanostructured Cobalt Ferrite: Modulating and Simulations toward Memory Devices.

Magnetic nanostructures with flux-closure state or single-domain state have widespread application in diverse memory devices. However, an insight into the modulation of these variable states within one specific magnetic material is rarely reported but still needed. Herein, these micromagnetic configurations within prototypical cobalt ferrite (CoFeO) nanostructures in different size and dimension were studied by modulating the assembly of CoFeO building blocks.

The magnetization reversal mechanism in electrospun tubular nickel ferrite: a chain-of-rings model for symmetric fanning.

Magnetic behaviors within nanoscopic materials are being widely explored due to their intriguing performance and widespread applications. Herein, we studied the magnetization reversal mechanism in a unique tubular nickel ferrite (NiFeO), in which the building blocks of NiFeO monocrystalline have a face-centered spinel structure and stack along the axial direction of the nanotube. We synthesized this tubular NiFeO through an electrospinning method based on a phase separation process, and then investigated the magnetization reversal process and its relationship with the morphologies using the model of "chain-of-rings" from the micromagnetism theory.

Achievement of Diverse Domain Structures in Soft Magnetic Thin Film through Adjusting Intrinsic Magnetocrystalline Anisotropy.

Oriented soft magnetic hcp-Co Ir films with a fixed thickness of 120 nm were fabricated. All prepared films exhibit soft magnetic properties but various magnetocrystalline anisotropies with the variation of Ir content. The measured data shows that diverse domain structures including the Néel wall, Bloch wall, and stripe domains present in a fixed film thickness.

Enhanced film thickness for Néel wall in soft magnetic film by introducing strong magnetocrystalline anisotropy.

This study investigated the magnetic domain walls in a single-layer soft magnetic film with strong magnetocrystalline anisotropy energy. The soft magnetic film is composed of a highly c-axis-oriented hcp-Co81Ir19 alloy with strong negative magnetocrystalline anisotropy. The domain structure of the soft Co81Ir19 films with thickness ranging from 50-230 nm in a demagnetization state was observed through magnetic force microscopy and Lorentz transmission electron microscopy.

1D magnetic materials of Fe₃O₄ and Fe with high performance of microwave absorption fabricated by electrospinning method.

Fe3O4 and Fe nanowires are successfully fabricated by electrospinning method and reduction process. Wiry microstructures were achieved with the phase transformation from α-Fe2O3 to Fe3O4 and Fe by partial and full reduction, while still preserving the wire morphology. The diameters of the Fe3O4 and Fe nanowires are approximately 50-60 nm and 30-40 nm, respectively.

Co@Co₃O₄ core-shell three-dimensional nano-network for high-performance electrochemical energy storage.

An alternative routine is presented by constructing a novel architecture, conductive metal/transition oxide (Co@Co3O4) core-shell three-dimensional nano-network (3DN) by surface oxidating Co 3DN in situ, for high-performance electrochemical capacitors. It is found that the Co@Co3O4 core-shell 3DN consists of petal-like nanosheets with thickness of <10 nm interconnected forming a 3D porous nanostructure, which preserves the original morphology of Co 3DN well. X-ray photoelectron spectroscopy by polishing the specimen layer by layer reveals that the Co@Co3O4 nano-network is core-shell-like structure.

Magnetic properties and spin dynamics in Ba(Fe(1-x)Mn(x))2As2 compounds studied by 57Fe Mössbauer spectroscopy.

Ba(Fe(1-x)Mn(x))2As2 compounds with x = 0.016 and 0.064 have been studied by (57)Fe Mössbauer spectroscopy in the temperature range from 30 to 300 K.

Nanoscale characterization and magnetic reversal mechanism investigation of electrospun NiFe2O4 multi-particle-chain nanofibres.

NiFe(2)O(4) multi-particle-chain nanofibres have been successfully fabricated using electrospinning followed by calcination, and their morphology, chemistry and crystal structure were characterized at the nanoscale. Individual NiFe(2)O(4) nanofibres were found to consist of many nanocrystallites stacked along the nanofibre axis. Chemical analysis shows that the atomic ratio of Ni : Fe is 1 : 2, indicating that the composition was NiFe(2)O(4).

BaFe12O19 single-particle-chain nanofibers: preparation, characterization, formation principle, and magnetization reversal mechanism.

BaFe(12)O(19) single-particle-chain nanofibers have been successfully prepared by an electrospinning method and calcination process, and their morphology, chemistry, and crystal structure have been characterized at the nanoscale. It is found that individual BaFe(12)O(19) nanofibers consist of single nanoparticles which are found to stack along the nanofiber axis. The chemical analysis shows that the atomic ratio of Ba/Fe is 1:12, suggesting a BaFe(12)O(19) composition.

Magnetic and structural properties of magnetite in radular teeth of chiton Acanthochiton rubrolinestus.

The teeth of the Polyplacophora Chiton Acanthochiton Rubrolinestus contain biomineralized magnetite crystallites whose biological functions in relation to structure and magnetic properties are not well understood. Here, using superconducting quantum interference device (SQUID) magnetometry, we find that the saturation magnetization (σ(s)) and the Verwey transition temperature (T(v)) of tooth particles are 78.4 emu/g and 105 K, respectively.

Synthesis and Magnetic Properties of Nearly Monodisperse CoFe2O4Nanoparticles Through a Simple Hydrothermal Condition.

Nearly monodisperse cobalt ferrite (CoFe2O4) nanoparticles without any size-selection process have been prepared through an alluring method in an oleylamine/ethanol/water system. Well-defined nanospheres with an average size of 5.5 nm have been synthesized using metal chloride as the law materials and oleic amine as the capping agent, through a general liquid-solid-solution (LSS) process.

Enhanced microwave absorption of Fe nanoflakes after coating with SiO2 nanoshell.

Fe nanoflakes were prepared by the ball-milling technique, and then were coated with 20 nm-thick SiO(2) to prepare Fe/SiO(2) core-shell nanoflakes. Compared with the uncoated Fe nanoflakes, the permittivity of Fe/SiO(2) nanoflakes decreases dramatically, while the permeability decreases slightly. Consequently, reflection losses exceeding - 20 dB of Fe/SiO(2) nanoflakes are obtained in the frequency range of 3.

Mesoporous nanowire array architecture of manganese dioxide for electrochemical capacitor applications.

Mesoporous MnO(2) nanowire array architecture exhibits enhanced capacitive and charge/discharge performance for electrochemical capacitors.