Adsorption of Helium atoms on two-dimensional substrates

Abstract

The study of the adsorption phenomenon of helium began many decades ago with the discovery of graphite as a homogeneous substrate for investigation of physically adsorbed monolayer films. In particular, helium monoatomic layers on graphite were found to exhibit a very rich phase diagram. In the present work we have investigated the adsorption phenomenon of helium atoms on graphene and silicene substrates by means of density functional theory with Born-Oppenheimer approximation. Helium-substrate and helium-helium interactions were considered from first principles. Vibrational properties of adsorbed monolayers have been used to explore the stability of the system. This approach reproduces results describing the stability of a helium monolayer on graphene calculated by quantum Monte Carlo (QMC) simulations for low and high coverage cases. However, for the moderate coverage value there is discrepancy with QMC results due to the lack of helium zero point motion.

References in corpus (7)

• Van der Waals Density Functional for General Geometries
• Epitaxial Growth of a Silicene Sheet
• Electronic structure of silicon-based nanostructures
• 4He on a single graphene sheet
• Path integral Monte Carlo simulation of the second layer of helium-4 adsorbed on graphite
• Thermodynamic Evidence for Nanoscale Bose-Einstein Condensation in ^4He Confined in Nanoporous Media
• Phase diagram of ${}^4$He on graphene

Cited by in corpus (4)

• Adsorption by design: tuning atom-graphene van der Waals interactions via mechanical strain
• Two-Dimensional Bose-Hubbard Model for Helium on Graphene
• Efficient simulations of Hartree--Fock equations by an accelerated gradient descent method
• Effects of substrate corrugation during helium adsorption on graphene in the grand canonical ensemble