收缩:在室温下在分子电线中的超高电磁阻
R N Mahato1, H Lülf, M H Siekman
1NanoElectronics Group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
Science (New York, N.Y.)
|July 6, 2013
概括
研究人员在非磁性分子电线中发现了超高磁阻 (MR) 效应. 这种由旋转阻塞驱动的室温现象对磁传感器和数据存储应用具有重大潜力.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 大型磁阻 (MR) 对于磁场传感和数据存储至关重要.
- 通常,大型MR效应依赖于材料的磁性特性.
- 对于实际应用来说,室温,小场的MR非常理想.
研究的目的:
- 调查非磁性系统中大型MR效应的可能性.
- 探索实现超高磁阻的新机制.
- 评估将分子电线用在地质石中用于MR应用的可行性.
主要方法:
- 使用嵌入在热带石宿主晶体中的分子电线制造一维系统.
- 在室温和在小磁场 (毫氏度范围) 中测量磁阻的实验测量.
- 理论分析以阐明导致观察到的MR效应的潜在物理机制.
主要成果:
- 在室温和小磁场中观察到异常大的磁阻效应 (>2000%).
- 观察到的MR效应存在于非磁性,一维分子电线系统中.
- 这种现象归因于一维电子运输中发生的自旋阻塞.
结论:
- 在非磁性系统中确定了一种实现超高电磁阻的新机制.
- 在低维系统中,自旋阻塞的通用性为MR应用开辟了新的途径.
- 这些发现为开发先进的磁传感器和数据存储设备提供了重大机会.
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