巨大的强制性在一个一维的基协调磁铁中的强制性
Norio Ishii1, Yoshitomo Okamura, Susumu Chiba
1Department of Applied Physics and Chemistry and Course of Coherent Optical Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan. ishi@pc.uec.ac.jp
Journal of the American Chemical Society
|December 14, 2007
概括
一种新的金属基聚合物表现出有史以来最高的强制场,在低温下起到异常硬的磁铁作用. 然而,由于磁化的快速变化,其磁性转变为10K以上的柔性.
科学领域:
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
- 聚合物化学 聚合物化学
背景情况:
- 开发先进的磁性材料对于技术创新至关重要.
- 金属基聚合物由于不配对的电子旋转而具有独特的磁性.
- 了解磁性行为的温度依赖性是材料应用的关键.
研究的目的:
- 为了合成和描述一种新的金属基聚合物.
- 为了研究合成聚合物的磁性,特别是强制性.
- 探索温度依赖的磁性行为和磁化动态.
主要方法:
- 合成了 (II) 双 (hexafluoroacetylacetonate) -双 (pyridyl) 基氧化物基聚合物 ([Co (hfac) 2.BPNN]) 的合成方法.
- 磁性性能测量包括歇斯底里循环来确定强制场.
- 温度依赖的磁性易感性和磁化研究.
主要成果:
- 金属基聚合物[Co(hfac) 2.BPNN]在6K时显示出创纪录的52kOe (4.1MA m-1) 的强制场.
- 这种特殊的强制性使该材料被归类为迄今为止报告的最硬的磁铁.
- 在10K以上,该材料表现出由于快速磁化重定向动态而产生的柔性磁性特性.
结论:
- 合成的金属基聚合物代表了硬磁材料的重大进步.
- 从硬磁向软磁的温度依赖的转变凸显了其磁性状态的动态性.
- 对控制磁化动态的进一步研究可能会导致在磁性存储和自旋电子学中的新应用.
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