title: Equilibrium long-ranged charge correlations at the surface of a conductor coupled to electromagnetic radiation.
abstract: This study is related to the fluctuation theory of electromagnetic fields, charges, and currents. The three-dimensional system under consideration is a semi-infinite conductor, modeled by the jellium, in vacuum. In previous theoretical studies it was found that the correlation functions of the surface charge density on the conductor decay as the inverse cube of the distance at asymptotically large distances. The prefactor to this asymptotic decay was obtained in the classical limit and in the quantum case without retardation effects. To describe the retarded regime, we study a more general problem of the semi-infinite jellium in thermal equilibrium with the radiated electromagnetic field. By using Rytov's fluctuational electrodynamics we show that, for both static and time-dependent surface charge correlation functions, the inclusion of retardation effects causes the quantum prefactor to take its universal static classical form, for any temperature.
authors.affiliation: Laboratoire de Physique Théorique, Université de Paris-Sud, 91405 Orsay Cedex, France. ladislav.samaj@savba.sk
authors.forename: Ladislav
authors.initials: L
authors.lastname: Samaj
authors.forename: Bernard
authors.initials: B
authors.lastname: Jancovici