FePt and Related Nanoparticles

  • J.W. Harrell
  • Shishou Kang
  • David E. Nikles
  • Gregory B. Thompson
  • Shifan Shi
  • Chandan Srivastava


This chapter reviews recent studies of chemically synthesized FePt and related nanoparticles. Various methods for synthesizing the nanoparticles and controlling their shape are described. Thermal effects in nanoparticles near the superparamagnetic limit are discussed. Some of the methods for reducing sintered grain growth during annealing to obtain the L10 phase are described, including the use of a hard shell, annealing in a salt matrix , and flash annealing . The effect of metal additives on the ordering temperature and on sintered grain growth is discussed. Additive Ag and Au significantly not only reduce the ordering temperature but also the grain growth temperature in close-packed 3-D arrays. Preliminary experiments that show additive Ag also reduces the ordering temperature when sintering is prevented. Easy-axis alignment of L10 FePt nanoparticles can be achieved by drying a nanoparticle dispersion in a magnetic field, and the effect of thermal fluctuations on orientation is discussed. Large particle-to-particle compositional distributions in chemically synthesized FePt nanoparticles have been measured. A method of determining the anisotropy distribution is described. Theoretical and experimental works showing the size effect on chemical ordering of FePt nanoparticles are discussed.


Oleyl Amine Composition Distribution FePt Nanoparticles Iron Pentacarbonyl Compositional Distribution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



nano-beam energy dispersed spectrometry


high-resolution transmission electron microscopy


strong coupling approximation


transmission electron microscopy








vibrating sample magnetometer


X-ray diffraction





This work has been supported by the NSF Materials Research Science and Engineering Center Award No. DMR-0213985.


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • J.W. Harrell
    • 1
  • Shishou Kang
    • 2
  • David E. Nikles
    • 3
  • Gregory B. Thompson
    • 4
  • Shifan Shi
    • 1
  • Chandan Srivastava
    • 4
  1. 1.Department of Physics & Center for Materials for Information TechnologyThe University of AlabamaTuscaloosaUSA
  2. 2.Center for Materials for Information TechnologyThe University of AlabamaTuscaloosaUSA
  3. 3.Department of Chemistry, Center for Materials for Information TechnologyThe University of AlabamaTuscaloosaUSA
  4. 4.Department of Metallurgical and Materials Engineering, Center for Materials for Information TechnologyThe University of AlabamaTuscaloosaUSA

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