Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20740, USA.
Nat Nanotechnol. 2012 Apr 8;7(5):316-9. doi: 10.1038/nnano.2012.39.
Minimizing Joule heating remains an important goal in the design of electronic devices. The prevailing model of Joule heating relies on a simple semiclassical picture in which electrons collide with the atoms of a conductor, generating heat locally and only in regions of non-zero current density, and this model has been supported by most experiments. Recently, however, it has been predicted that electric currents in graphene and carbon nanotubes can couple to the vibrational modes of a neighbouring material, heating it remotely. Here, we use in situ electron thermal microscopy to detect the remote Joule heating of a silicon nitride substrate by a single multiwalled carbon nanotube. At least 84% of the electrical power supplied to the nanotube is dissipated directly into the substrate, rather than in the nanotube itself. Although it has different physical origins, this phenomenon is reminiscent of induction heating or microwave dielectric heating. Such an ability to dissipate waste energy remotely could lead to improved thermal management in electronic devices.
将焦耳热最小化仍然是电子设备设计中的一个重要目标。目前的焦耳热模型依赖于一个简单的半经典图像，即电子与导体的原子发生碰撞，在局部产生热量，而且只在非零电流密度的区域产生热量，这一模型得到了大多数实验的支持。然而，最近有人预言，石墨烯和碳纳米管中的电流可以与相邻材料的振动模式耦合，从而远程加热材料。在这里，我们使用原位电子热显微镜探测到单根多壁碳纳米管对氮化硅衬底的远程焦耳加热。施加到纳米管上的电力中至少有 84%直接耗散到衬底中，而不是耗散在纳米管本身中。尽管其物理起源不同，但这种现象类似于感应加热或微波介电加热。这种远程耗散废热的能力可能会提高电子设备的热管理水平。
