Simulations of Gas-, Liquid-, and Crystal-Like States of Coulomb Systems

Abstract

As example, we consider application of the theoretical approach discussed in the last chapter to treatment of a partially ionized strongly coupled dense electron-hole plasma. We take into account strong Coulomb correlation effects such as bound states (excitons, bi-excitons, clusters), their modification by the surrounding plasma, and their eventual breakup at high densities due to pressure ionization (Mott effect). Beyond the Mott density, we expect the possibility of hole crystallization if the hole mass is sufficiently large (Boniz et al. 2005). We consider the results of direct path integral Monte Carlo simulations for a broad range of hole-to-electron mass ratios, temperatures, and densities. The density of the two-component plasma is characterized by the Brueckner parameter $r_\mathrm{s}$, defined as the ratio of the mean distance between particles and the exciton Bohr $\mathrm{d}= [3=4_(n_{e} + n_{h})]1=3$ radius. We discuss the spatial particle configurations, pair distribution functions, static structure factors, fractions of electrons and holes in bound states, internal energy, and equation of state.