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Independent particle descriptions of tunneling from a many-body perspective

Giorgos Fagas·Paul Delaney·James C. Greer
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Abstract

Currents across thin insulators are commonly taken as single electrons moving across classically forbidden regions; this independent particle picture is well-known to describe most tunneling phenomena. Examining quantum transport from a different perspective, i.e., by explicit treatment of electron-electron interactions, we evaluate different single particle approximations with specific application to tunneling in metal-molecule-metal junctions. We find maximizing the overlap of a Slater determinant composed of single particle states to the many-body current-carrying state is more important than energy minimization for defining single particle approximations in a system with open boundary conditions. Thus the most suitable single particle effective potential is not one commonly in use by electronic structure methods, such as the Hartree-Fock or Kohn-Sham approximations.

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Giorgos Fagas, Paul Delaney, James C. Greer. 2006-06-01. Independent particle descriptions of tunneling from a many-body perspective. https://doi.org/10.1103/physrevb.73.241314

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