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arXiv · 0706.0140

Treatment of electron viscosity in quantum conductance

J. Jung·P. Bokes·R. W. Godby
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Abstract

In a recent paper Sai {\it et al.} [1] identified a correction $R^{dyn}$ to the DC conductance of nanoscale junctions arising from dynamical exchange-correlation ($XC$) effects within time-dependent density functional theory. This quantity contributes to the total resistance through $R=R_{s}+R^{dyn}$ where $R_{s}$ is the resistance evaluated in the absence of dynamical $XC$ effects. In this Comment we show that the numerical estimation of $R^{dyn}$ in example systems of the type they considered should be considerably reduced, once a more appropriate form for the shear electron viscosity $η$ is used.

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J. Jung, P. Bokes, R. W. Godby. 2007-06-01. Treatment of electron viscosity in quantum conductance. https://doi.org/10.1103/physrevlett.98.259701

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