An efficient tight-binding model including magnetism and spin-orbit interactions is extended to metallic alloys. The tight-binding parameters are determined from a fit to bulk ab initio calculations of each metal and rules are given to obtain the heteroatomic parameters. The spin and orbital magnetic moments as well as the magneto-crystalline anisotropy are derived. We apply this method to bulk FePt L1(0) and the results are compared with success to ab initio results where available. Finally this model is applied to a set of FePt L1(0) clusters and physical trends are derived.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1088/0953-8984/24/40/406004 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Wide Linearity Range 3D Magnetic Sensor and Angular Position Detector Based on a Single FePt Spin-Orbit Torque Device.
ACS Appl Mater Interfaces
May 2024
School of Automation, China University of Geosciences, Wuhan 430074, China.
Three-dimensional (3D) vector magnetic sensors play a significant role in a variety of industries, especially in the automotive industry, which enables the control of precise position, angle, and rotation of motion elements. Traditional 3D magnetic sensors integrate multiple sensors with their sensing orientations along the three coordinate axes, leading to a large size and inevitable nonorthogonal misalignment. Here, we demonstrate a wide linearity range 3D magnetic sensor utilizing a single 1-FePt Hall-bar device, whose sensitivity is 291 VA T in the -axis and 27 VA T in the in-plane axis.
View Article and Find Full Text PDFBias sputtering of granular L1-FePt films with hexagonal boron nitride grain boundaries.
Sci Rep
July 2023
Data Storage Systems Center, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
In this paper, we present an experimental study of L1-FePt granular films with crystalline boron nitride (BN) grain boundary materials for heat assisted magnetic recording (HAMR). It is found that application of a RF substrate bias (V = -15 V) yields the formation of hexagonal boron nitride (h-BN) nanosheets in grain boundaries, facilitating the columnar growth of FePt grains during sputtering at high temperatures. The h-BN monolayers conform to the side surfaces of columnar FePt grains, completely encircling individual FePt grains.
View Article and Find Full Text PDFNovel Rare Earth (RE)-Free Nanocomposite Magnets Derived from L1-Phase Systems.
Nanomaterials (Basel)
March 2023
National Institute for Materials Physics, P.O. Box MG-7, 077125 Magurele, Romania.
In the quest for novel rare earth (RE)-free magnetic materials, which also exhibit other additional properties such as good corrosion resistance and potential to operate at higher temperatures, an alloy deriving from the binary FePt system, with Mo and B addition, has been synthesized for the first time, using the out-of-equilibrium method of rapid solidification form the melt. The alloy with the composition FePtMoB has been subjected to thermal analysis through differential scanning calorimetry in order to detect the structural disorder - order phase transformation as well as to study the crystallization processes. For the stabilization of the formed hard magnetic phase, the sample has been annealed at 600 °C and further structurally and magnetically characterized by means of X-ray diffraction, transmission electron microscopy, Fe Mössbauer spectrometry as well as magnetometry experiments.
View Article and Find Full Text PDFSynthesis of L1 -Iron Triad (Fe, Co, Ni)/Pt Intermetallic Electrocatalysts via a Phosphide-Induced Structural Phase Transition.
Adv Mater
February 2023
State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Structurally ordered L1 -iron triad (Fe, Co, Ni)/Pt with a M(iron triad)/Pt ratio ≈1:1 has drawn increasing attention in oxygen reduction reaction (ORR) electrocatalysis and fuel cell technologies by virtue of the high performance derived from their strong surface strain. However, the synthesis of intermetallic L1 -M(iron triad)Pt generally requires the accurate content control of the multicomponent and the sufficient thermal energy to overcome the kinetic barrier for atom diffusion. This work reports a synthesis of sub ≈5 nm L1 -intermetallic nanoparticles using phosphide intermediate-induced structural phase transition.
View Article and Find Full Text PDFNonequilibrium sub-10 nm spin-wave soliton formation in FePt nanoparticles.
Sci Adv
April 2022
Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden.
Magnetic nanoparticles such as FePt in the L1 phase are the bedrock of our current data storage technology. As the grains become smaller to keep up with technological demands, the superparamagnetic limit calls for materials with higher magnetocrystalline anisotropy. This, in turn, reduces the magnetic exchange length to just a few nanometers, enabling magnetic structures to be induced within the nanoparticles.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!