共掺杂的锰铁氧体纳米颗粒：磁各向异性与颗粒间相互作用

Aslibeiki Bagher, Kameli Parviz, Salamati Hadi, Concas Giorgio, Salvador Fernandez Maria, Talone Alessandro, Muscas Giuseppe, Peddis Davide

Department of Physics, University of Tabriz, Tabriz 51666-16471, Iran.

Department of Physics, Isfahan University of Technology, Isfahan, 84156-83111, Iran.

Beilstein J Nanotechnol. 2019 Apr 12;10:856-865. doi: 10.3762/bjnano.10.86. eCollection 2019.

The effect of cobalt doping on the magnetic properties of Mn Co FeO nanoparticles was investigated. All samples consist of ensembles of nanoparticles with a spherical shape and average diameter of about 10 nm, showing small structural changes due to the substitution. Besides having the same morpho-structural properties, the effect of the chemical composition, i.e., the amount of Co doping, produces marked differences on the magnetic properties, especially on the magnetic anisotropy, with evident large changes in the coercive field. Moreover, Co substitution has a profound effect on the interparticle interactions, too. A dipolar-based interaction regime is detected for all samples; in addition, the intensity of the interactions shows a possible relation with the single particle anisotropy. Finally, the sample with the strongest interaction regime shows a superspin glass state confirmed by memory effect dynamics.

研究了钴掺杂对Mn Co FeO纳米颗粒磁性的影响。所有样品均由平均直径约为10 nm的球形纳米颗粒聚集体组成，由于替代作用显示出微小的结构变化。除了具有相同的形态结构特性外，化学成分的影响，即钴掺杂量，对磁性产生了显著差异，尤其是对磁各向异性，矫顽场有明显的大变化。此外，钴替代对颗粒间相互作用也有深远影响。所有样品均检测到基于偶极的相互作用机制；此外，相互作用的强度显示出与单颗粒各向异性可能存在的关系。最后，具有最强相互作用机制的样品显示出通过记忆效应动力学证实的超自旋玻璃态。