2025/06/17 by Jean‐Christophe Pain, Pain, Jean-Christophe, Mikael Tacu +1
Chemical Engineering · Computer Science · #FOS: Physical sciences #Neural Networks and Applications #Plasma Physics (physics.plasm-ph) #Thermodynamic properties of mixtures
paper · pdf · doi:10.48550/arxiv.2506.14941
openalex publication_date 2025/06/17 · openalex created_date 2025/10/19 · openalex updated_date 2026/07/28
In order to obtain the frequency-dependent photo-absorption in a plasma, both the real and imaginary parts of the AC conductivity are required. The real part can be deduced from the knowledge of the static conductivity (given by the Ziman-Evans formula for instance) and the Drude model. The imaginary part, required for the refraction index, can be obtained using the Kramers-Kronig relations. Usually, it is obtained by complex integration in the complex plane of the usual Kramers-Kronig relations, having ω'-ω in the denominator. However, an alternate form of the Kramers-Kronig relation is often used in physics, especially for determining response functions. It has ω'2-ω2 in the denominator. We provide two determinations of the imaginary part of the conductivity for this latter form, one using a decomposition into simple elements, and the other involving a complex integration in a quarter of the complex plane.