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arXiv · 1904.12582

Exact real-time dynamics of single-impurity Anderson model from a single-spin hybridization-expansion

Patryk Kubiczek·Alexey N. Rubtsov·Alexander I. Lichtenstein
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Abstract

In this work we introduce a modified real-time continuous-time hybridization-expansion quantum Monte Carlo solver for a time-dependent single-orbital Anderson impurity model: CT-1/2-HYB-QMC. In the proposed method the diagrammatic expansion is performed only for one out of the two spin channels, while the resulting effective single-particle problem for the other spin is solved semi-analytically for each expansion diagram. CT-1/2-HYB-QMC alleviates the dynamical sign problem by reducing the order of sampled diagrams and makes it possible to reach twice as long time scales in comparison to the standard CT-HYB method. We illustrate the new solver by calculating an electric current through impurity in paramagnetic and spin-polarized cases.

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Patryk Kubiczek, Alexey N. Rubtsov, Alexander I. Lichtenstein. 2019-04-29. Exact real-time dynamics of single-impurity Anderson model from a single-spin hybridization-expansion. https://doi.org/10.21468/scipostphys.7.2.016

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