单分子电子:使用交叉结合物种增加动态范围和切换速度
David Q Andrews1, Gemma C Solomon, Richard P Van Duyne
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA. dqandrews@u.northwestern.edu
Journal of the American Chemical Society
|December 5, 2008
概括
分子电子利用交叉结合的分子来创建高性能开关和设备. 这些分子中的量子干扰使电子功能和新型设备应用具有很大的动态范围.
科学领域:
- 分子电子学分子电子学
- 量子化学是一种量子化学.
- 纳米技术纳米技术
背景情况:
- 积极的电子元素在分子尺度上被寻求,以与固态性能竞争.
- 设计分子开关需要了解电子传输动态.
研究的目的:
- 研究分子开关和设备的理想设计.
- 分析交叉结合的分子如何使电子传输具有很大的动态范围.
- 探索分子晶体管和整流器中的应用.
主要方法:
- 在交叉合分子中分析传输图谱.
- 电子运输现象的计算建模.
- 分子电子元件的设计和模拟.
主要成果:
- 交叉结合的分子表现出显著的动态范围在电子传输概率由于干扰.
- 展示了对干扰特征 (宽度,深度,能量) 的控制操作.
- 一个单分子晶体管显示了8级的导电率变化.
- 一个分子整流器实现了超过15万的整流比.
- 纯电子负差电阻被计算出来.
结论:
- 交叉结合分子中的量子干扰为高性能分子电子设备提供了一条途径.
- 通过电子密度变化实现的大动态范围使快速稳定的切换成为可能.
- 这些发现为新型分子晶体管,整流器和其他电子元件铺平了道路.
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