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Quantum conductance of homogeneous and inhomogeneous interacting electron systems

P. Bokes·J. Jung·R. W. Godby
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Abstract

We obtain the conductance of a system of electrons connected to leads, within time-dependent density-functional theory, using a direct relation between the conductance and the density response function. Corrections to the non-interacting conductance appear as a consequence of the functional form of the exchange-correlation kernel at small frequencies and wavevectors. The simple adiabatic local-density approximation and non-local density-terms in the kernel both give rise to significant corrections in general. In the homogeneous electron gas, the former correction remains significant, and leads to a failure of linear-response theory for densities below a critical value.

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P. Bokes, J. Jung, R. W. Godby. 2006-04-12. Quantum conductance of homogeneous and inhomogeneous interacting electron systems. https://arxiv.org/abs/cond-mat/0604317

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