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arXiv · 1810.10509

Auxiliary master equation for nonequilibrium dual-fermion approach

Feng Chen·Guy Cohen·Michael Galperin
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Abstract

We introduce auxiliary quantum master equation - dual fermion approach (QME-DF) and argue that it presents a convenient way to describe steady-states of correlated impurity systems. The combined scheme yields an expansion around a reference much closer to the true nonequilibrium state than in the original dual fermion formulation. In steady-state situations, the scheme is numerically cheaper and allows to avoid long time propagation of previous considerations. Anderson impurity is used as a test model. The QME-DF simulations are compared with numerically exact tdDMRG results.

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Feng Chen, Guy Cohen, Michael Galperin. 2018-10-24. Auxiliary master equation for nonequilibrium dual-fermion approach. https://doi.org/10.1103/physrevlett.122.186803

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