Recent Submissions

  • Rapid thermal annealing of FePt nanoparticles 

    Nandwana, Vikas; Yano, Kazuaki; Poudyal, Narayan; Rong, Chuan-Bing; Liu, J. Ping (AIP, 2008-07-01)
    We report a systematic study on rapid thermal annealing (RTA) of FePt nanoparticles. FePt particles with an average size of 8 nm were synthesized by a chemical solution method, and then annealed using RTA and conventional ...
  • High thermal stability of carbon-coated L10-FePt nanoparticles prepared by salt-matrix annealing 

    Nandwana, Vikas; Rong, Chuan-Bing; Poudyal, Narayan; Chaubey, Girija S.; Liu, Yuzi; Wu, Y.Q.; Kramer, M.J.; Kozlov, M.E.; Baughman, R.H.; Liu, J. Ping (AIP, 2008)
    Monodisperse L10-FePt nanoparticles with size ranging from 3 to 8 nm were prepared by the salt-matrix annealing method. It was observed that the annealed particles have high thermal stability—no sintering occurred even ...
  • Structural phase transition and ferromagnetism in monodisperse 3 nm FePt particles 

    Nandwana, Vikas; Rong, Chuan-bing; Chaubey, Girija S.; Skomski, R; Wu, Y.Q.; Kramer, M.J.; Liu, J. Ping (AIP, 2007)
    FePt nanoparticles with a size of 3 nm and thermally stable room-temperature ferromagnetism are investigated. The monodisperse nanoparticles were prepared by chemical synthesis and a salt-matrix annealing technique. ...
  • Bulk FePt-based nanocomposite magnets with enhanced exchange coupling 

    Nandwana, Vikas; Liu, J. Ping; Poudyal, Narayan; Rong, Chuan-Bing; Kozlov, Mikhail E.; Baughman, Ray H.; Ding, Yong; Wang, Zhong Lin (AIP, 2007)
    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 ...
  • Microstructures and magnetic alignment of L10 FePt nanoparticles 

    Nandwana, Vikas; Kang, Shishou; Shi, Shifan; Jia, Zhiyong; Thompson, G.B.; Nikles, David E.; Harrell, J.W.; Poudyal, Narayan; Liu, J. Ping (AIP, 2009)
    Chemically ordered FePt nanoparticles were obtained by high temperature annealing a mixture of FePt particles with NaCl. After the NaCl was removed with de-ionized water, the transformed FePt nanoparticles were redispersed ...
  • Bulk FePt/Fe3Pt nanocomposite magnets prepared by spark plasma sintering 

    Nandwana, Vikas; Rong, Chuan-Bing; Poudyal, Narayan; Liu, J. Ping; Saito, Tetsuji; Wu, Yaqiao; Kramer, Matthew J. (AIP, 2007)
    FePt/Fe3Pt bulk nanocomposite magnets have been prepared by the spark plasma sintering of chemically synthesized FePt and Fe3O4 nanoparticles under 100 MPa at 400–600 °C. It was found that the phase transition of the FePt ...
  • Hard magnetic FePt nanoparticles by salt-matrix annealing 

    Nandwana, Vikas; Li, Daren; Poudyal, Narayan; Jin, Zhiqiang; Elkins, Kevin; Liu, J Ping (AIP, 2006)
    To transfer face-centered-cubic (fcc) FePt nanoparticles to the face-centered-tetragonal (fct) phase with high magnetic anisotropy, heat treatments are necessary. The heat treatments lead to agglomeration and sintering of ...