The dc magnetic susceptibility vs curves measured from particles processed at under 1 and 10 bar oxygen. The particle size is 160 nm under both conditions.
X-ray diffraction pattern of the 160 nm powder refined by Rietveld method.
TEM micrographs of nanoparticles calcined under 10 bar oxygen at (a) and (b) .
Temperature dependence of the dc susceptibility for powders with different sizes. The measurement was performed at .
Magnetic hysteresis loops at 5 K for the 60, 95, and 160 nm particles and the bulk ceramic.
Temperature dependence of the ac susceptibility for powders with different sizes measured at 1 Hz field. (a) The real part . (b) The imaginary part .
Temperature dependence of the dc susceptibility for the as-calcined 160 nm powder and the 160 nm powder annealed at 800 and .
(a) Close view of the vs hysteresis loops in nanoparticles shown in Fig. 5. Inset: the exchange bias and coercivity of the nanoparticles as a function of the particle size. (b) Close view of the vs hysteresis loops of 60 nm nanoparticles measured at 5 K under ZFC, 8 kOe FC, and −8 kOe FC conditions, respectively. Inset: the exchange bias of nanoparticles with different particle sizes under ZFC, 8 kOe FC, and −8 kOe FC conditions.
Lattice parameters determined by Rietveld refinement for the nanoparticles processed under 10 bar oxygen.
Magnetic parameters derived from hysteresis loops at 5 K.
Article metrics loading...
Full text loading...