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arXiv · 2201.06103

Non-perturbative $ab$ $initio$ approach for calculating the electrical conductivity of a liquid metal

Abstract

We propose a non-perturbative $ab$ $initio$ approach to calculate the electrical conductivity of a liquid metal. Our approach is based on the Kubo formula and the theory of electron-phonon coupling (EPC), and unlike the conventional empirical approach based on the Kubo-Greenwood formula, fully takes into account the effect of coupling between electrons and moving ions. We show that the electrical conductivity at high temperature is determined by an EPC parameter $λ_{\mathrm{tr}}$, which can be inferred, non-perturbatively, from the correlation of electron scattering matrices induced by ions. The latter can be evaluated in a molecular dynamics simulation. Based on the density-functional theory and pseudopotential methods, we implement the approach in an $ab$ $initio$ manner. We apply it to liquid sodium and obtain results in good agreement with experiments. This approach is efficient and based on a rigorous theory, suitable for applying to general metallic liquid systems.

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Xiao-Wei Zhang, Haoran Chen, En-Ge Wang, Junren Shi, Xin-Zheng Li. 2022-01-16. Non-perturbative $ab$ $initio$ approach for calculating the electrical conductivity of a liquid metal. https://doi.org/10.1103/physrevb.105.155148

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