Advances in magnetic films of epsilon-iron oxide toward next-generation high-density recording media.

  title={Advances in magnetic films of epsilon-iron oxide toward next-generation high-density recording media.},
  author={Hiroko Tokoro and Asuka Namai and Shin‐ichi Ohkoshi},
  journal={Dalton transactions},
Iron oxide magnets, which are composed of the common elements iron and oxygen, are called ferrite magnets. They have diverse applications because they are chemically stable and inexpensive. Epsilon-iron oxide (ε-Fe2O3) is a polymorph that shows an extremely large coercive field as a magnetic oxide. It maintains its ferromagnetic ordering even when downsized to a single nano-sized scale (i.e.,<10 nm). Due to these characteristics, ε-Fe2O3 is highly expected to be used for high-density magnetic… 
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Large Coercive Field of 45 kOe in a Magnetic Film Based on Metal-Substituted ε-Iron Oxide.
This study prepared a rhodium-substituted ε-iron oxide film and observed a remarkably large Hc value of 35 kOe at room temperature, which is the largest value among magnetic ferrites to date.
Hard magnetic ferrite with a gigantic coercivity and high frequency millimetre wave rotation
It is shown that rhodium-substituted ε-Fe2O3,ε-RhxFe2−xO3 nanomagnets prepared by a nanoscale chemical synthesis using mesoporous silica as a template, exhibit a huge coercive field (Hc) of 27 kOe at room temperature, which is the largest value among metal-oxide-based magnets and is comparable to those of rare-earth magnets.
Mesoscopic bar magnet based on ε-Fe2O3 hard ferrite
From the viewpoint of the large coercive field property, it is demonstrated that a mesoscopic ε-Fe2O3 bar magnet can be used as a magnetic force microscopy probe.
Multimetal-Substituted Epsilon-Iron Oxide ϵ-Ga0.31 Ti0.05 Co0.05 Fe1.59 O3 for Next-Generation Magnetic Recording Tape in the Big-Data Era.
The magnetic tape media was fabricated using an actual production line and showed a very sharp signal response and a remarkably high signal-to-noise ratio compared to the currently used magnetic tape.
Unveiling a New High-Temperature Ordered Magnetic Phase in ε-Fe2O3
Iron oxides are among the most abundant materials on Earth, and yet there are some of their basic properties which are still not well-established. Here, we present temperature-dependent magnetic,
Nanometer-size hard magnetic ferrite exhibiting high optical-transparency and nonlinear optical-magnetoelectric effect
A single-nanosize hard magnetic ferrite, composed of ε-Fe2O3, with a sufficiently high Hc value for magnetic recording systems and a remarkably high magnetic anisotropy constant, is reported in a simple iron oxide.
Magnetic thin films of cobalt nanocrystals encapsulated in graphite-like carbon
A VARIETY of crystalline materials have now been encapsulated in nanometre-scale graphitic cages1–8 and tubules9–11. For magnetic materials, encapsulation should serve the dual role of protecting
Magnetic hyperthermia with ε-Fe2O3 nanoparticles
Biocompatibility restrictions have limited the use of magnetic nanoparticles for magnetic hyperthermia therapy to iron oxides, namely magnetite (Fe3O4) and maghemite (γ-Fe2O3). However, there is yet
High- and Low-Temperature Crystal and Magnetic Structures of ε-Fe2O3 and Their Correlation to Its Magnetic Properties
The crystal and magnetic structures of orthorhombic e-Fe2O3 have been studied by simultaneous Rietveld refinement of X-ray and neutron powder-diffraction data in combination with Mossbauer