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"Screening" of universal van der Waals - Casimir terms by Coulomb gases in a fully-finite two-dimensional geometry

B. Jancovici·L. Samaj
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Abstract

This paper is a continuation of a previous one [Jancovici and Samaj, 2004 J. Stat. Mech. P08006] dealing with classical Casimir phenomena in semi-infinite wall geometries. In that paper, using microscopic Coulomb systems, the long-ranged Casimir force due to thermal fluctuations in conducting walls was shown to be screened by the presence of an electrolyte between the walls into some residual short-ranged force. Here, we aim to extend the study of the screening (cancellation) phenomena to universal Casimir terms appearing in the large-size expansions of the grand potentials for microscopic Coulomb systems confined in fully-finite 2D geometries, in particular the disc geometry. Two cases are solved exactly: the high-temperature (Debye-Hückel) limit and the Thirring free-fermion point. Similarities and fundamental differences between fully-finite and semi-infinite geometries are pointed out.

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B. Jancovici, L. Samaj. 2005-05-17. "Screening" of universal van der Waals - Casimir terms by Coulomb gases in a fully-finite two-dimensional geometry. https://doi.org/10.1088/1742-5468%2F2005%2F05%2Fp05004

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