Variational approach to transport in quantum dots

Nicola Lanatà

doi:10.1103/physrevb.82.195326

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arXiv · 0911.1292

Variational approach to transport in quantum dots

Nicola Lanatà

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Abstract

We have derived a variational principle that defines the nonequilibrium steady-state transport across a correlated impurity mimicking, e.g., a quantum dot coupled to biased leads. This variational principle has been specialized to a Gutzwiller's variational space, and applied to the study of the simple single-orbital Anderson impurity model at half filling, finding a good qualitative accord with the observed behavior in quantum dots for the expected regime of values of the bias. Beyond the purely theoretical interest in the formal definition of a variational principle in a nonequilibrium problem, the particular methods proposed have the important advantage to be simple and flexible enough to deal with more complicated systems and variational spaces.

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Nicola Lanatà. 2011-02-14. Variational approach to transport in quantum dots. https://doi.org/10.1103/physrevb.82.195326

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