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Transport in nanoscale systems: the microcanonical versus grand-canonical picture

M. Di Ventra·T. N. Todorov
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Abstract

We analyse a picture of transport in which two large but finite charged electrodes discharge across a nanoscale junction. We identify a functional whose minimisation, within the space of all bound many-body wavefunctions, defines an instantaneous steady state. We also discuss factors that favour the onset of steady-state conduction in such systems, make a connection with the notion of entropy, and suggest a novel source of steady-state noise. Finally, we prove that the true many-body total current in this closed system is given exactly by the one-electron total current, obtained from time-dependent density-functional theory.

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M. Di Ventra, T. N. Todorov. 2004-07-20. Transport in nanoscale systems: the microcanonical versus grand-canonical picture. https://doi.org/10.1088/0953-8984%2F16%2F45%2F024

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