大型室温磁电阻在高旋转的捐赠-接受结合聚合物中
Hamas Tahir1, Naresh Eedugurala2, Sheng-Ning Hsu1
1Charles D. Davidson School of Chemical Engineering, Purdue University, 480 W. Stadium Ave, West Lafayette, IN, 47907, USA.
Advanced materials (Deerfield Beach, Fla.)
|November 1, 2023
概括
开的合聚合物在低温下表现出巨大的负磁电阻,超过有机材料的性能. 这种基于旋转的传输现象,在一种新型的捐赠-接受聚合物中观察到,为电子应用提供了新的途径.
科学领域:
- 有机电子学有机电子学
- 材料科学是一种材料科学.
- 这就是Spintronics.
背景情况:
- 由于其独特的特性,开联聚合物 (CPs) 对基于旋转的技术具有前景.
- 了解CP中电子结构和传输现象之间的关系对于其应用至关重要.
- 现有的半导体材料缺乏光元素组成,弱自旋轨道合和CP提供的解决方案可加工性的综合属性.
研究的目的:
- 为了在高旋转的供体-接受体CP中建立分子,电子和固态运输之间的第一个相关性.
- 为了研究一种新型结合聚合物的取决于温度的磁电阻 (MR) 行为.
- 阐明电子和旋转结构在CP中调制MR中的作用.
主要方法:
- 合成和制造高旋转供体接受器CP的薄膜装置.
- 可变温度的磁电阻测量.
- 电子偏磁共振光谱学和磁感应度测量.
主要成果:
- 在薄膜装置中,在10K时达到98%的巨大负磁电阻 (MR),超过了所有其他有机材料.
- 阴性MR随着温度的增加而下降,在180K以上变为正值,室温MR为13.5%.
- 对MR信号和大小的调制与CP的电子和旋转结构直接相关.
结论:
- 具有开放外和高旋转基态的捐赠者-接受者CP为新兴的基于旋转的应用提供了重大机会.
- 观察到的温度依赖的MR行为凸显了这些材料在可调节电子设备中的潜力.
- 这项研究提供了对高旋转合聚合物的结构性质关系的关键见解,用于旋转电子学.
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