1. High Temperature Magnetic Stabilization of Cobalt Nanoparticles by an Antiferromagnetic Proximity Effect.

    Physical Review Letters 115(5):057201 (2015) PMID 26274435

    Thermal activation tends to destroy the magnetic stability of small magnetic nanoparticles, with crucial implications for ultrahigh density recording among other applications. Here we demonstrate that low-blocking-temperature ferromagnetic (FM) Co nanoparticles (T(B)<70  K) become magnetically s...
  2. Life on magnets: stem cell networking on micro-magnet arrays.

    PLoS ONE 8(8):e70416 (2013) PMID 23936425 PMCID PMC3731273

    Interactions between a micro-magnet array and living cells may guide the establishment of cell networks due to the cellular response to a magnetic field. To manipulate mesenchymal stem cells free of magnetic nanoparticles by a high magnetic field gradient, we used high quality micro-patterned Nd...
  3. Evolutionary conservation of early mesoderm specification by mechanotransduction in Bilateria.

    Nature Communications 4:2821 (2013) PMID 24281726 PMCID PMC3868206

    The modulation of developmental biochemical pathways by mechanical cues is an emerging feature of animal development, but its evolutionary origins have not been explored. Here we show that a common mechanosensitive pathway involving β-catenin specifies early mesodermal identity at gastrulation i...
  4. Size dependence of exchange bias in Co/CoO nanostructures.

    Physical Review Letters 108(7):077205 (2012) PMID 22401249

    In Co/CoO nanostructures, of dimensions l×3l, at small Co thickness (≈6,10 nm), a strong increase in the bias field and the associated coercive field are found as the nanostructure size is reduced from l=120 nm to l=30 nm. This property indicates that the characteristic length D(AF) within the a...
  5. Electric field-induced modification of magnetism in thin-film ferromagnets.

    Science 315(5810):349 (2007) PMID 17234941

    A large electric field at the surface of a ferromagnetic metal is expected to appreciably change its electron density. In particular, the metal's intrinsic magnetic properties, which are commonly regarded as fixed material constants, will be affected. This requires, however, that the surface has...
  6. Exchange coupling mechanism for magnetization reversal and thermal stability of Co nanoparticles embedded in a CoO matrix

    Journal of Magnetism and Magnetic Materials 294(2):111 (2005)

    A model providing a semi-quantitative account of the magnetic behavior of Co nanoparticles embedded in a CoO matrix is presented. The results confirm that exchange coupling at the interface between ferromagnetic (FM) and antiferromagnetic (AFM) nanostructures could provide an extra source o...
  7. Beating the superparamagnetic limit with exchange bias.

    Nature 423(6942):850 (2003) PMID 12815426

    Interest in magnetic nanoparticles has increased in the past few years by virtue of their potential for applications in fields such as ultrahigh-density recording and medicine. Most applications rely on the magnetic order of the nanoparticles being stable with time. However, with decreasing part...
  8. Preparation of microstructured and nanostructured magnetic materials by mechanical deformation

    Journal of Magnetism and Magnetic Materials 242:581 (2002)

    A novel hydrostatic extrusion process utilising sacrificial Al billets has been developed to allow the size reduction by deformation of samples of various cross-sectional shape (e.g. square, rectangular). Cyclic deformation of a stack of sub-mm thick foils of magnetic and non-magnetic metal...
  9. Magnetism of intermetallics

    Current Opinion in Solid State & Materials Science 1(2):183 (1996)

    Original properties were recently discovered in itinerant electron systems , for example , reentrant ferromagnetsm in RMn 2GE 2, and weak ferromagnetism in PdTiAl, when the composition elements are individually non-magnetic. In rare earth-transi- tion metal compounds (RM), the s...