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arXiv · 2305.01452

Heating and cooling in self-consistent many-body simulations

Yang Yu·Sergei Iskakov·Emanuel Gull
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Abstract

We present a temperature extrapolation technique for self-consistent many-body methods, which provides a causal starting point for converging to a solution at a target temperature. The technique employs the Carath\'eodory formalism for interpolating causal matrix-valued functions and is applicable to various many-body methods, including dynamical mean field theory, its cluster extensions, and self-consistent perturbative methods such as the self-consistent GW approximation. We show results that demonstrate that this technique can efficiently simulate heating and cooling hysteresis at a first-order phase transition, as well as accelerate convergence.

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Yang Yu, Sergei Iskakov, Emanuel Gull. 2023-05-02. Heating and cooling in self-consistent many-body simulations. https://doi.org/10.1103/physrevb.108.155116

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