电子道进入铁电表面的极化控制
Peter Maksymovych1, Stephen Jesse, Pu Yu
1Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA. maksymovychp@ornl.gov
Science (New York, N.Y.)
|June 13, 2009
概括
研究人员使用自发偏振来控制铁电材料中的电子传输. 这种铁电开关将道电流放大了500倍,从而实现了潜在的数据存储和自旋电子应用.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 铁电材料表现出自发的电极化,可以通过外部电场切换.
- 控制纳米电子运输对于开发先进电子设备至关重要.
- 酸酸 (Pb(Zr0.2Ti0.8) O3或PZT) 是一个著名的铁电性矿,具有显著的自发极化.
研究的目的:
- 为了证明在铁电氧化膜中对局部电子传输的可重复控制.
- 为了研究铁电极化开关对电子道电流的影响.
- 探索数据存储和自旋电子技术的潜在应用.
主要方法:
- 使用原子力显微镜 (AFM) 将电子注入到薄的PZT膜中.
- 在高电场下的福勒-诺德海姆道系统中运行.
- 测量和分析道电流歇斯底里及其与铁电开关的相关性.
主要成果:
- 通过自发极化实现了通过自发极化实现局部电子运输的高度可重现的控制.
- 在道电流中观察到明显的歇斯底里,与与铁电极化开关同步的突然切换事件.
- 由于铁电开关,证明了道电流的 500 倍放大.
- 通过铁电开关展示了这种效应的静电控制.
结论:
- 在铁电PZT薄膜中的局部电子传输可以通过操纵自发极化来有效控制.
- 铁电切换显著放大了电子道电流,为新的电子功能提供了一个有希望的机制.
- 演示的控制和放大显示了超高密度数据存储和先进的自旋电子设备的潜力.
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