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arXiv · 2606.02890

Kinetic Theory for Electronic Transport Properties of Warm Dense Matter: Chapman-Enskog Solution of the Uehling-Uhlenbeck Equation

Lucas J. Babati·Nathaniel R. Shaffer·Louis Jose·Scott D. Baalrud
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Abstract

A kinetic theory is developed to describe the electrical conductivity, thermal conductivity, and electrothermal coefficients in warm dense plasmas. It models electron degeneracy using the Uehling-Uhlenbeck equation, diffraction by computing scattering cross sections quantum mechanically, and strong coupling by treating the scattering events using the potential of mean force. A key advancement detailed here is the development of a Chapman-Enskog solution of the Uehling-Uhlenbeck equation for hydrodynamic transport coefficients. The result is a model which accurately predicts transport coefficients spanning from warm dense matter conditions through hot dilute plasmas, including the influence of electron-electron interactions. Results are compared with quantum molecular dynamics simulations, experiments, and other models. The present method is able to capture the ''Spitzer'' terms in the classical plasma limit, while also capturing the correct degenerate limit. The transition between these limits in the warm dense matter regime is explained in terms of the availability of states for electron scattering.

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Lucas J. Babati, Nathaniel R. Shaffer, Louis Jose, Scott D. Baalrud. 2026-06-01. Kinetic Theory for Electronic Transport Properties of Warm Dense Matter: Chapman-Enskog Solution of the Uehling-Uhlenbeck Equation. https://arxiv.org/abs/2606.02890

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