Thermoelectricity: A Bottom-up View

It is well-known that the nature of electronic transport changes significantly as the length L of the active region of a device is reduced from millimeter down to nanometer dimensions. Historically our understanding of electrical resistance and conduction has progressed top-down: from large macroscopic conductors to small atomic scale conductors. Indeed thirty years ago it was common to argue about what, if anything, the concept of resistance meant on an atomic scale. Since then there has been significant progress in our understanding, spurred by actual experimental measurements made possible by the technology of miniaturization. However, despite this progress in understanding the flow of current on an atomic scale, the standard approach to the problem of electronic transport continues to be top-down and we have argued elsewhere that an alternative bottom-up viewpoint can be extremely illuminating [1]. In this talk we will briefly summarize this viewpoint and discuss the unique insights it provides into the subject of thermoelectricity and thermoelectric device design in general and into the possibilities of molecular thermoelectrics in particular. \\[4pt] [1] See for example, S.Datta, ``Nanolectronic Devices: A Unified View,'' to appear in The Oxford Handbook on Nanoscience and Nanotechnology: Frontiers and Advances, eds. A.V. Narlikar and Y.Y. Fu, volume 1, chapter 1, arXiv/0809.4460