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arXiv · 2309.02198

Average-atom Ziman resistivity calculations in expanded metallic plasmas: effect of mean ionization definition

Nadine Wetta·Jean-Christophe Pain
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Abstract

We present calculations of electrical resistivity for expanded boron, aluminum, titanium and copper plasmas using the Ziman formulation in the framework of the average-atom model. Our results are compared to experimental data, as well as with other theoretical calculations, relying on the Ziman and Kubo-Greenwood formulations, and based on average-atom models or quantum-molecular-dynamics simulations. The impact of the definition of ionization, paying a particular attention to the consistency between the latter and the perfect free electron gas assumption made in the formalism, is discussed. We propose a definition of the mean ionization generalizing to expanded plasmas the idea initially put forward for dense plasmas, consisting in dropping the contribution of quasi-bound states from the ionization due to continuum ones. It is shown that our recommendation for the calculation of the quasi-bound density of states provides the best agreement with measurements.

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Nadine Wetta, Jean-Christophe Pain. 2023-09-05. Average-atom Ziman resistivity calculations in expanded metallic plasmas: effect of mean ionization definition. https://arxiv.org/abs/2309.02198

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