MONTE-CARLO SIMULATIONS OF THE CHARGED BOSON FLUID AT T=0

The diffusion Monte Carlo (DMC) method is used to analyze various prop erties of the three-dimensional plasma of charged bosons in the homoge neous fluid regime, over the density range 1 less than or equal to r(s ) less than or equal to 160 extending from the so-called uniform limit (r(s)<1) to the crystalline phase (r(s)>160). The data on the static density response function chi(k) extend to intermediate and high wave number k the work of Sugiyama, Bowen, and Alder [Phys. Rev. B 46, 13 0 42 (1999)] and allow us to extract the static local-held factor G(k) f or exchange and correlation. The DMC results for the momentum distribu tion n(k) show that the condensate fraction decreases with increasing coupling strength from 83% at r(s)=1 to less than 1% at r(s)=160. We a lso present results for the ground-state energy E(g)(r(s)) and for the structure factor S(k). The results for E(g)(r(s)), n(k), and chi(k) a re summarized in analytic interpolation formulas embodying the known a symptotic behaviors. A rigorous upper bound on the plasmon dispersion curve is obtained from the DMC data through a sum-rule argument.