High density bulk FePt/Fe3Pt nanocomposite magnets have been prepared by high-pressure warm compaction of chemically synthesized FePt and Fe3O4 nanoparticles. It is found that the density increases with the compaction pressure and temperature. Density of the bulk samples up to 95% theoretical value has been obtained while the nanostructured morphology is retained. It is also observed that a hig...

Thickness modulation at the edges of nanostructured magnetic thin films is shown to have important effects on their perpendicular magnetic anisotropy. Thin film wires with tapered edges were made from [Co/Pd]20 multilayers or L10-FePt films using liftoff with a double-layer resist. The effect of edge taper on the reversal process was studied using magnetic force microscopy (MFM) and micromagnet...

Monatomic (Fe, Co) and bimetallic (FePt and CoPt) nanoparticles were prepared by exploiting the self-organization of precursor loaded reverse micelles. Achievements and limitations of the preparation approach are critically discussed. We show that self-assembled metallic nanoparticles can be prepared with diameters d = 2-12 nm and interparticle distances D = 20-140 nm on various substrates. Str...

The electrocatalytic oxidation of formic acid at a gold electrode functionalized with FePt nanoparticles was studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in a mixed solution of 0.1 M HCOOH and 0.1 M HClO4. The FePt bimetallic nanoparticles, with a mean diameter of 3 nm, were prepared by a chemical reduction method. The Au/FePt nanostructured electrode was ...

We report the formation mechanism of FePt nanoparticles (NPs) by a high temperature polyol method using an equimolar ratio of Fe and Pt-precursor with different Pt-precursors. Pt(acac)2, PtCl2, PtCl4 and H2PtCl6·H2O were used as Pt-precursors and Fe(acac)3 as the only Fe-precursor. Different stoichiometric compositions along with variation in size were obtained by using different precursors of ...

This study investigated the ultrathin Cu(002) capping nano-island effects on magnetic characterizations and microstructure of epitaxial FePt(001) films directly fabricated MgO(001) substrates at relatively low temperature 300 °C via electron-beam deposition. The enhancement coercivity is attributed to lowered exchange coupling FePt grains that begun from Cu atom behavior spreading in many direc...

S. Anders,, M. F. Toney, T. Thomson, J.-U. Thiele, and B. D. Terris IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120 Shouheng Sun, and C. B. Murray IBM T. J. Watson Research Center, Yorktown Heights, NY 10598 a) Electronic mail: [email protected] Monodisperse FePt nanoparticles were prepared using high temperature solution phase synthesis. Polymer-mediated layer-by-layer gro...

OBJECTIVES Affect identification accuracy paradigms have increasingly been utilized to understand psychiatric illness including Bipolar Disorder (BD) and Major Depressive Disorder (MDD). This investigation focused on perceptual accuracy in affect identification in both visual and auditory domains among patients with BD, relative to Healthy Controls (HC) and patients with MDD. Demographic and cl...

A thin FePt film was deposited onto a CrV seed layer at 400°C and showed a high coercivity (~3,400 Oe) and high magnetization (900-1,000 emu/cm(3)) characteristic of L 10 phase. However, the magnetic properties of patterned media fabricated from the film stack were degraded due to the Ar-ion bombardment. We employed a deposition-last process, in which FePt film deposited at room temperature und...

The complex correlation of structure and magnetism in highly coercive monoatomic FePt surface alloys is studied using scanning tunneling microscopy, x-ray magnetic circular dichroism, and ab initio theory. Depending on the specific lateral atomic coordination of Fe either hard magnetic properties comparable to that of bulk FePt or complex noncollinear magnetism due to Dzyaloshinski-Moriya inter...