Phase diagram of the two-dimensional Coulomb gas: A thermodynamic scaling Monte Carlo study

In this work, we report results for the phase diagram of the two-dimensional Coulomb system. We use a recently proposed simulation method, thermodynamic scaling Monte Carlo, to determine the Kosterlitz–Thouless insulator/conductor transition line and the first-order vapor–liquid coexistence curve. The Kosterlitz–Thouless line terminates at the first-order coexistence curve close to the gas–liquid critical point. Our estimate of the vapor–liquid critical point is, T*≊0.056, ρ*≊0.21, in only modest agreement with previous theoretical estimates and semiquantitative numerical results.