The Properties of Spin Valves with a Partially Oxidized Fe or CoFe Ultra-Thin Layer Inserted in the Magnetic Layers

  • In, Jang-sik (Materials Science and Engineering, Yonsei University) ;
  • Han,Yoon-sung (Materials Science and Engineering, Yonsei University) ;
  • Kim, Sung-hoon (Materials Science and Engineering, Yonsei University) ;
  • Shim, Jae-chul (Materials Science and Engineering, Yonsei University) ;
  • Hong, Jong-ill (Materials Science and Engineering, Yonsei University)
  • Published : 2006.09.01


Co-ferrite nanoparticles have been synthesized by the decomposition of iron(III) acetylacetonate, $Fe(acac)_3$ and Co acetylacetonate, $Co(acac)_2$ in benzyl/phenyl ether in the presence of oleic acid and oleyl amine at the refluxingtemperature of $295^{\circ}C$/$265^{\circ}C$ for 30 min. before cooling to room temperature. Particle diameter detected by PSA can be turned from 4 nm to 20 nm by seed-mediated growth and reaction conditions. Structural and magneticcharacterization of Co-ferrite were measured by use of HRTEM, SAED (selected area electron diffraction), XRD and SQUID. The as-synthesized Co-ferrite nanoparticles have a cubic spinel structure and coercivity of 20 nm $CoFe_{2}O_{4} nanoparticles reached 1 kOe at room temperature and 18 kOe at 10 K.


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