Center for Solid State Physics and New Materials, Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia.
J Phys Condens Matter. 2012 Nov 14;24(45):456001. doi: 10.1088/0953-8984/24/45/456001. Epub 2012 Oct 17.
We have measured the magnetization of undoped and Fe(2+/3+) doped CeO(2-y) nanocrystals at various temperatures and magnetic fields. The Stoner condition N(0)I > 1 is multiply fulfilled in the case of nano-CeO(2-y), favoring the band ferromagnetism approach. In the case of Fe-doped samples, the magnetization versus magnetic field dependence is well fitted with a weighted Langevin function. A blocking temperature of about 20 K is obtained both from the ZFC/FC curves and from the coercive field against temperature dependence. The temperature and field dependence of the magnetization clearly shows the presence of nanosized particles which exhibit superparamagnetic behavior.
我们测量了不同温度和磁场下未掺杂和 Fe(2+/3+)掺杂的 CeO(2-y)纳米晶的磁化强度。在纳米 CeO(2-y)的情况下，满足 Stoner 条件 N(0)I > 1，有利于带铁磁性方法。对于 Fe 掺杂的样品，磁化强度与磁场的关系很好地符合加权朗之万函数。从 ZFC/FC 曲线和矫顽场随温度的关系得到约 20 K 的阻塞温度。磁化强度的温度和磁场依赖性清楚地表明存在具有超顺磁性行为的纳米颗粒。
