Bridge functions in strongly coupled plasmas
theory, simulations and applications
Time: Fri 2021-12-10 14.00
Location: Ångdomen, Osquars backe 31, Stockholm
Language: English
Subject area: Theoretical Physics Atomic, Subatomic and Astrophysics
Doctoral student: Federico Castello Lucco , Rymd- och plasmafysik
Opponent: Associate professor Giorgio Pastore, Department of Physics, Università degli Studi di Trieste, Italy
Supervisor: Professor Svetlana V. Ratynskaia, Rymd- och plasmafysik; Dr. Panagiotis Tolias, Rymd- och plasmafysik
QC 20211117
Abstract
Strongly coupled or non-ideal plasmas are multi-component charged systems in which at least one species possesses an average interaction energy that is comparable or larger than its thermal energy. Non-ideal plasmas are naturally occurring in dense astrophysical objects (e.g. giant planet interiors) but also engineered in the laboratory (e.g. plasma discharges seeded with solid particulates). They are typically encountered in the liquid state, whose theoretical description is particularly challenging due to the lack of small parameters. This thesis is focused on the development of a novel theoretical approach for the accurate calculation of the structural and thermodynamic properties of plasma liquids. Apart from their inherent significance, these properties also constitute necessary input to advanced theories of dynamical correlations, collective excitations and transport coefficients. The theoretical approach is based on the integral equation theory framework, whose central quantity is the bridge function; an abstract object of diagrammatic analysis that is impossible to calculate or even approximate through virial-type expansions. Here the bridge function is accurately determined by combining elements of the isomorph theory of R-simple liquids with indirect extractions from computer simulations. The unprecedented level of accuracy in both the structural and thermodynamic properties and the very low computational cost, render the approach the most efficient alternative to computer simulations of classical and quantum plasma liquids. Applications to collective modes and metastable properties are also discussed.