超快闪的分子链的热导电
Zhaohui Wang1, Jeffrey A Carter, Alexei Lagutchev
1School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Science (New York, N.Y.)
|August 11, 2007
概括
分子中的热传输是通过振动发生的,而不是经典概念. 这项研究观察了以1公里/秒的速度沿碳化合物链的弹道热流,揭示了分子导电率极限,这对分子电子学至关重要.
科学领域:
- 分子动力学分子动力学
- 凝聚物质物理学 凝聚物质物理学
- 纳米级的传热方式
背景情况:
- 经典的热传输模型在分子层面上失败.
- 分子系统中的能量转移对于分子电子学至关重要.
- 分子振动刺激在纳米级热传输中携带能量.
研究的目的:
- 研究分子链中的热传输机制.
- 在分子尺度上量化热流和导电.
- 了解分子振动在热能转移中的作用.
主要方法:
- 超快速激光加热金基板.
- 通过碳化合物分子的自我组装单层研究热传输.
- 非线性连贯振动光谱检测热障碍.
主要成果:
- 热转移到分子链中受界面导电量限制.
- 观察到沿碳化合物链以1公里/秒的速度进行弹道热传播.
- 测量的分子导电量为50皮卡瓦特/克尔文/链.
结论:
- 分子热传输是由振动激发控制的.
- 弹道热传输发生在纳米级沿着分子链.
- 接口导电性和分子结构决定了热传输效率.
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