有机自旋中的巨大的磁阻
Z H Xiong1, Di Wu, Z Valy Vardeny
1Department of Physics, University of Utah, Salt Lake City, Utah 84112, USA.
Nature
|February 27, 2004
概括
研究人员在有机旋转中展示了巨大的磁电阻. 这一突破使用pi-结合的有机半导体进行自旋极化载体运输,为新的自旋电子设备铺平了道路.
科学领域:
- 这就是Spintronics.
- 有机电子学有机电子学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 旋转利用自旋依赖的电子传输用于磁记录和内存中的应用.
- 金属旋转中的巨型磁阻 (GMR) 和道磁阻 (TMR) 推动了旋转电子学领域的发展.
- 将自旋电子效应扩展到半导体是一个活跃的研究领域,在无机材料方面取得了进展,但没有证明具有半导体间隔器的自旋装置.
研究的目的:
- 研究pi-结合有机半导体作为旋结构中的间隔层的潜力.
- 为了在基于有机半导体的旋中实现旋极化载体注入,运输和检测.
- 为了在有机旋装置中展示巨大的磁阻效应.
主要方法:
- 使用pi结合有机半导体作为间隔层制造一个旋结构.
- 在不同磁场下对自旋偏振载体行为和电阻的实验研究.
- 低温测量以描述磁阻效应的特征.
主要成果:
- 通过有机半导体间隔器成功注入,运输和检测自旋极化载体.
- 观察到显著的低温巨型磁阻效应,高达40%.
- 使用有机半导体组件的功能旋装置的演示.
结论:
- 联有机半导体是用于自旋电子应用的可行材料,在自旋中起到有效的间隔层的作用.
- 在有机自旋中观察到的巨大的磁阻力为开发有机自旋电子设备开辟了新的途径.
- 这项工作是实现使用有机材料的半导体自旋电子技术的重要一步.
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