Current partition: Nonequilibrium Green's function Approach

TL;DR

This paper introduces a comprehensive nonequilibrium Green's function approach to accurately analyze AC current partition in multi-probe mesoscopic conductors, accounting for interactions and arbitrary frequencies.

Contribution

It generalizes previous theories by removing frequency limitations and enabling detailed interaction treatments within the NEGF formalism.

Findings

Derived dynamic conductance for mesoscopic systems

Validated the formalism with tunneling structure calculations

Ensured current conservation and gauge invariance

Abstract

We present a solution to the problem of AC current partition in a multi-probe mesoscopic conductor within the nonequilibrium Green's function formalism. This allows the derivation of dynamic conductance which is appropriate for nonequilibrium situations and which satisfies the current conservation and gauge invariance requirements. This formalism presents a significant generalization to previous theory: (i) there is no limit in the frequency, and (ii) it allows detailed treatments of interactions in the mesoscopic region. The formalism is applied to calculate dynamic conductance of tunneling structures with and without assuming wideband limit.