Stability of a Nondegenerate Two--Component Weakly Coupled Plasma

The paper discusses the problem of stability of a two-component plasma and proposes a consistent consideration of quantum and long-range effects to calculate the thermodynamic properties of such a plasma. We restrict ourselves by the case of a non-degenerate plasma to avoid the fermionic sign problem and consider the weakly coupled regime. Long-range interaction effects are taken into account using the angular-averaged Ewald potential (AAEP). To calculate thermodynamic properties, we apply both classical Monte Carlo (CMC) and path integral Monte Carlo (PIMC) methods. A special method is developed to correctly calculate potential energy in PIMC simulations with long-range interaction effects. Our theoretical estimations show that the probability of a bound state formation is very low at a coupling parameter $\Gamma~\le~0.01$, so both classical and quantum simulations give the same energy at $\Gamma~\leq~0.01$, and the thermodynamic limit coincides with the Debye--H\"uckel theory. At higher $\Gamma$, the $N$-convergence is lost due to the formation of bound states.