Path-integral calculation of the two-dimensional He phase diagram
نویسندگان
چکیده
Path-integral Monte Carlo simulations have been used to determine the phase diagram of a two-dimensional He film in a range of temperatures and coverages where it undergoes solidification, superfluidity, and a liquid-gas transition (0.25 K<T<1.5 K 0,s,0.094 Å). We determine the phase-transition densities and give the coefficients for a functional form of the free energy in the liquid, solid, and gas phases. The phase diagram is similar to the one determined from experimental measurements of a second layer of helium on graphite. @S0163-1829~98!04634-7#
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