Density-functional theory of nonequilibrium tunneling
Journal article, 2008

Nanoscale optoelectronics and molecular-electronics systems operate with current injection and nonequilibrium tunneling—phenomena that challenge consistent descriptions of the steady-state transport. The current affects the electron-density variation and hence the intermolecular and intramolecular bondings which in turn determine the transport magnitude. The standard approach for efficient characterization of steady-state tunneling combines ground-state density-functional theory (DFT) calculations (of an effective scattering potential) with a Landauer-type formalism and ignores all actual many-body scattering. The standard method also lacks a formal variational basis. This paper formulates a Lippmann-Schwinger (LS) collision density-functional theory (LSC DFT) for tunneling transport with full electron-electron interactions. Quantum-kinetic (Dyson) equations are used for an exact reformulation that expresses the variational noninteracting and interacting many-body scattering T matrices in terms of universal density functionals. The many-body LS variational principle defines an implicit equation for the exact nonequilibrium density.

Lippmann-Schwinger variational principle


density-functional theory

nonequilibrium tunneling

T-matrix calculations


Per Hyldgaard

Chalmers, Applied Physics, Electronics Material and Systems

Physical Review B - Condensed Matter and Materials Physics

24699950 (ISSN) 24699969 (eISSN)

Vol. 78 16 165109-

Areas of Advance

Nanoscience and Nanotechnology

Materials Science


Basic sciences

Subject Categories

Other Physics Topics

Condensed Matter Physics



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