Path Integral Monte Carlo Simulations of Thin 4 He Films on a H 2 Surface
نویسنده
چکیده
Atomically thin 4 He lms of up to three monolayers on molecular hydrogen (1,1,1) surfaces are studied at T=0.5 K, using path integral Monte Carlo. We compute the binding energy of 4 He to the H 2 substrate as a function of 4 He coverage and obtain evidence of the prewetting transition. Density pro les perpendicular to the 4 He-H 2 interface are obtained, as well as the zero point motion and e ective mass of 4 He parallel to the substrate surface. The super uid density of 4 He vs: coverage is calculated, and the intermediate scattering function is computed, from which we estimate the speed of third sound. Finally, we calculate the vorticity-vorticity correlation function.
منابع مشابه
Path Integral Monte Carlo Simulations of H 2 Surfaces
The (1,1,1)-surfaces of bulk solid molecular hydrogen have been studied at temperatures between 0.5K and 1.3K, using path integral Monte Carlo. A general method is introduced for constructing an external potential to represent the tail correction for an arbitrary heterogeneous layered bulk substrate-adsorbate system. We compute density pro les parallel and perpendicular to the free H 2 surface,...
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