Puddles of helium in two dimensions: A Monte Carlo study

In this paper we report simulation studies of two-dimensional puddles of liquid ⁴He, using variational wave functions. We extract the line tension of these puddles and the energy in the bulk. We also study the surface profile and width of the surface region of the puddles as a function of system size. The wave functions are used to investigate the binding of boson ³He. We find that mass-3 bosons are very weakly self-bound in two dimensions and fermions of the same mass are very unlikely to bind. Further we believe that a monolayer film of ³He on graphite will not bind into a liquid puddle; it would be a gas at low densities and a solid at very high densities.