arXiv:1405.0756 · Physical Review B

Transport of correlated electrons through disordered chains: A perspective on entanglement, conductance, and disorder averaging

Daniel Karlsson, Claudio Verdozzi

Published Nov 18, 2014• 9 citations

Abstract

We investigate electron transport in disordered Hubbard chains contacted to macroscopic leads, via the nonequilibrium Green's function technique. We observe a crossover of currents and conductances at finite bias which depends on the relative strength of disorder and interactions. We provide a proof that the coherent potential approximation, a widely used method for treating disorder averages, fulfills particle conservation at finite bias with or without electron correlations. Finally, our results hint that the observed trends in conductance due to interactions and disorder also appear as signatures in the single-site entanglement entropy.

DOI: 10.1103/physrevb.90.201109

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