Novel Attractive Force Between Ions in Quantum Plasmas

TL;DR

This paper uncovers a new attractive force between ions in quantum plasmas, caused by quantum effects, leading to potential ion lattice formation and phase transitions at nanoscales.

Contribution

It introduces a novel attractive potential in quantum plasmas derived from quantum hydrodynamics, considering quantum statistical pressure, Bohm potential, and electron correlations.

Findings

Identification of a Lennard-Jones-like negative potential around ions

Potentially explains ion lattice formation in quantum plasmas

Implications for phase transitions at nanoscales

Abstract

We report new attractive force between ions that are shielded by degenerate electrons in quantum plasmas. Specifically, we show that the electric potential around an isolated ion has a hard core negative part that resembles the Lennard-Jones (LJ)-type potential. Physically, the new electric potential is attributed to the consideration of the quantum statistical pressure, the quantum Bohm potential, as well as the electron exchange and electron correlations due to electron-1/2 spin within the framework of the quantum hydrodynamical description of quantum plasmas. The shape of the attractive potential is determined by the ratio between the Bohr radius and the Wigner-Seitz radius of degenerate electrons. The existence of the hard core negative potential will be responsible for the attraction of ions forming lattices and atoms/molecules, as well as for critical points and phase transitions in quantum plasmas at nanoscales.