Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Department of Physics and Jiujiang Research Institute, Xiamen University, Xiamen 361005, China.
Phys Rev Lett. 2018 Dec 14;121(24):247704. doi: 10.1103/PhysRevLett.121.247704.
Controlling the direction and magnitude of both heat and electronic currents using rectifiers has significant implications for the advancement of molecular circuit design. In order to facilitate the implementation of new transport phenomena in such molecular structures, we examine thermal and thermoelectric rectification effects that are induced by an electron transfer process that occurs across a temperature gradient between molecules. Historically, the only known heat conduction mechanism able to generate thermal rectification in purely molecular environments is phononic heat transport. Here, we show that electron transfer between molecular sites with different local temperatures can also generate a thermal rectification effect and that electron hopping through molecular bridges connecting metal leads at different temperatures gives rise to asymmetric Seebeck effects, that is, thermoelectric rectification, in molecular junctions.
利用整流器控制热流和电流的方向和大小对分子电路设计的发展具有重要意义。为了在这些分子结构中实现新的输运现象,我们研究了由分子间温度梯度引起的电子转移过程所诱导的热和热电整流效应。从历史上看,在纯分子环境中唯一已知的能够产生热整流的热传导机制是声子热输运。在这里,我们表明,不同局部温度的分子位点之间的电子转移也可以产生热整流效应,而电子通过连接不同温度金属引线的分子桥的跳跃则会导致分子结中的不对称塞贝克效应,即热电整流。