SCREENED ION-ION INTERACTION POTENTIAL IN DENSE PLASMAS

Abstract

Quantum plasma has been the subject of active theoretical and experimental research
over the past few decades. The development of laser and accelerator technology, it is soon expected to
obtain a dense plasma with quantum ions. In this regard, this article presents the screened potential of
the interaction of ions, taking into account their wave nature, i.e. taking into account the diffraction
effect. At the considered parameters, the electrons are strongly degenerate. To take into account electron
degeneracy, we used the quantum electron response function in the random-phase approximation. Given
that the electrons at the densities under consideration are ideal, we used the expansion of the electron
density-density response function, up to and including the third term, in the long-wavelength limit. The
graphs of the obtained ion-ion interaction potential for various plasma parameters are presented. The
obtained ion interaction potential has a finite value at small distances due to the diffraction effect, i.e.
wave nature of ions manifested in non-locality. At large distances, the derived potential is screened, and
the screening differs from the Thomas-Fermi screening. The relationship of the used dielectric
permittivity method based on the density-density response function to other methods, such as quantum
hydrodynamics and the theory of density functionals, is discussed.