Monte Carlo simulations of the charged boson fluid atT=0

The diffusion Monte Carlo (DMC) method is used to analyze various properties of the three-dimensional plasma of charged bosons in the homogeneous fluid regime, over the density range 1{≤}rₛ{≤}160 extending from the so-called uniform limit (rₛ1) to the crystalline phase (rₛ{}160). The data on the static density response function {χ}(k) extend to intermediate and high wave number k the work of Sugiyama, Bowen, and Alder [Phys. Rev. B 46, 13 042 (1992)] and allow us to extract the static local-field factor G(k) for exchange and correlation. The DMC results for the momentum distribution n(k) show that the condensate fraction decreases with increasing coupling strength from 83% at rₛ=1 to less than 1% at rₛ=160. We also present results for the ground-state energy Eg(rₛ) and for the structure factor S(k). The results for Eg(rₛ), n(k), and {χ}(k) are summarized in analytic interpolation formulas embodying the known asymptotic behaviors. A rigorous upper bound on the plasmon dispersion curve is obtained from the DMC data through a sum-rule argument. {} 1996 The American Physical Society.