He-3 on preplated graphite

By using the diffusion Monte Carlo method, we obtained the full phase diagram of He3 on top of graphite preplated with a solid layer of He4. All the He4 atoms of the substrate were explicitly considered and allowed to move during the simulation. We found that the ground state is a liquid of density...

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Bibliographic Details
Authors: Gordillo Bargueño, Maria Carmen|||0000-0003-1521-483X, Boronat Medico, Jordi|||0000-0002-0273-3457
Format: article
Publication Date:2016
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/104458
Online Access:https://hdl.handle.net/2117/104458
https://dx.doi.org/10.1103/PhysRevB.94.165421
Access Level:Open access
Keyword:Monte Carlo method
Graphite
3He
Graphite preplated
Montecarlo, Mètode de
Grafit
Àrees temàtiques de la UPC::Física
Description
Summary:By using the diffusion Monte Carlo method, we obtained the full phase diagram of He3 on top of graphite preplated with a solid layer of He4. All the He4 atoms of the substrate were explicitly considered and allowed to move during the simulation. We found that the ground state is a liquid of density 0.007±0.001 Å-2, in good agreement with available experimental data. This is significantly different from the case of He3 on clean graphite, in which both theory and experiment agree on the existence of a gas-liquid transition at low densities. Upon an increase in He3 density, we predict a first-order phase transition between a dense liquid and a registered 7/12 phase, the 4/7 phase being found metastable in our calculations. At larger second-layer densities, a final transition is produced to an incommensurate triangular phase.