Crystallization in two-component Coulomb systems

TL;DR

This paper extends Coulomb crystallization analysis from one-component to two-component plasmas, deriving critical parameters for classical and quantum crystals, predicting hole crystallization in semiconductors, and presenting a unified phase diagram supported by simulations.

Contribution

It introduces a comprehensive analysis of two-component Coulomb crystals, including critical parameters and phase diagrams, with novel predictions for hole crystallization in semiconductors.

Findings

Critical mass ratio for quantum crystals is about 80.

Predicted spontaneous ordering of holes in semiconductors.

Verified phase diagram through first-principle simulations.

Abstract

The analysis of Coulomb crystallization is extended from one-component to two-component plasmas. Critical parameters for the existence of Coulomb crystals are derived for both classical and quantum crystals. In the latter case, a critical mass ratio of the two charged components is found which is of the order of 80. Thus, holes in semiconductors with sufficiently flat valence bands are predicted to spontaneously order into a regular lattice. Such hole crystals are intimately related to ion Coulomb crystals in white dwarf and neutron stars as well as to ion crystals produced in the laboratory. A unified phase diagram of two-component Coulomb crystals is presented and is verified by first-principle computer simulations.