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arXiv · 2311.02623

Towards out of equilibrium impurity solver for the Dynamical Mean Field Theory

A. Karpov·G. Sultanov·E. Polyakov·A. Rubtsov
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Abstract

The Dynamical Mean Field Theory (DMFT) is a powerful tool for calculating highly correlated systems (both bosonic and fermionic) in a state of thermodynamic equilibrium. However, in the case of non-equilibrium states, the method has significant limitations that do not allow obtaining correct results. The stumbling block here is the impurity solver: a method for calculating the dynamics of an open system. In this work we present the prototype of a universal impurity solver for the DMFT method which can solve both equilibrium and non-equilibrium problems. We analyse spectral functions of Bose-Hubbard model on the Bethe lattice in different regimes and show that our solver gives correct and physical results.

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A. Karpov, G. Sultanov, E. Polyakov, A. Rubtsov. 2023-11-05. Towards out of equilibrium impurity solver for the Dynamical Mean Field Theory. https://arxiv.org/abs/2311.02623

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