文章基本信息

标题：Exceeding natural resonance frequency limit of monodisperse Fe₃O₄ nanoparticles via superparamagnetic relaxation
本地全文：下载
作者：Ning-Ning Song ; Hai-Tao Yang ; Hao-Liang Liu 等
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2013
卷号：3
DOI：10.1038/srep03161
出版社：Springer Nature
摘要：Magnetic nanoparticles have attracted much research interest in the past decades due to their potential applications in microwave devices. Here, we adopted a novel technique to tune cut-off frequency exceeding the natural resonance frequency limit of monodisperse Fe₃O₄ nanoparticles via superparamagnetic relaxation. We observed that the cut-off frequency can be enhanced from 5.3 GHz for Fe₃O₄ to 6.9 GHz forFe₃O₄@SiO₂ core-shell structure superparamagnetic nanoparticles, which are much higher than the natural resonance frequency of 1.3 GHz for Fe₃O₄ bulk material. This finding not only provides us a new approach to enhance the resonance frequency beyond the Snoek's limit, but also extend the application for superparamagnetic nanoparticles to microwave devices.