Ground-state properties and superfluidity of two- and quasi two-dimensional solid 4He

Abstract

In a recent study we have reported a new type of trial wave function symmetric under the exchange of particles and which is able to describe a supersolid phase. In this work, we use the diffusion Monte Carlo method and this model wave function to study the properties of solid 4He in two- and quasi two-dimensional geometries. In the purely two-dimensional case, we obtain results for the total ground-state energy and freezing and melting densities which are in good agreement with previous exact Monte Carlo calculations performed with a slightly different interatomic potential model. We calculate the value of the zero-temperature superfluid fraction ρ_{s} / ρof 2D solid 4He and find that it is negligible in all the considered cases, similarly to what is obtained in the perfect (free of defects) three-dimensional crystal using the same computational approach. Interestingly, by allowing the atoms to move locally in the perpendicular direction to the plane where they are confined to zero-point oscillations (quasi two-dimensional crystal) we observe the emergence of a finite superfluid density that coexists with the periodicity of the system.

16 pages, 8 figures

References in corpus (7)

• Luttinger Liquid in the Core of Screw Dislocation in Helium-4
• Ring exchanges and the supersolid phase of 4He
• Phase diagram of 4He adsorbed on graphite
• 4He on a single graphene sheet
• Bose-Einstein Quantum Statistics and the Ground State of Solid 4He
• Atomic kinetic energy, momentum distribution and structure of solid neon at zero-temperature
• Two-dimensional molecular para-hydrogen and ortho-deuterium at zero temperature

Cited by in corpus (6)

• Supersolidity in quantum films adsorbed on graphene and graphite
• The elastic constants of solid 4He under pressure: a diffusion Monte Carlo study
• First-principles modeling of three-body interactions in highly compressed solid helium
• Possible superfluidity of molecular hydrogen in a two-dimensional crystal phase of sodium
• On the existence of supersolid helium-4 monolayer films
• Saga of Superfluid Solids