Título:
|
Possible superfluidity of molecular hydrogen in a two-dimensional crystal phase of sodium
|
Autor/a:
|
Cazorla Silva, Claudio; Boronat Medico, Jordi
|
Otros autores:
|
Universitat Politècnica de Catalunya. Departament de Física i Enginyeria Nuclear; Universitat Politècnica de Catalunya. SIMCON - Grup de Recerca de Simulació per Ordinador en Matèria Condensada |
Abstract:
|
We theoretically investigate the ground-state properties of a molecular para-hydrogen (p-H 2 ) film in which crystallization is energetically frustrated by embedding sodium (Na) atoms periodically distributed in a triangular lattice. In order to fully deal with the quantum nature of p-H 2 molecules, we employ the diffusion Monte Carlo method and realistic semiempirical pairwise potentials describing the interactions between H 2 -H 2 and Na-H 2 species. In particular, we calculate the energetic, structural, and superfluid properties of two-dimensional Na-H 2 systems within a narrow density interval around equilibrium at zero temperature. In contrast to previous computational studies considering other alkali metal species such as rubidium and potassium, we find that the p-H 2 ground state is a liquid with a significantly large superfluid fraction of ρ s /ρ=0.29(2) . The appearance of p-H 2 superfluid response is due to the fact that the interactions between Na atoms and H 2 molecules are less attractive than between H 2 molecules. This induces a considerable reduction of the hydrogen density which favors the stabilization of the liquid phase. |
Materia(s):
|
-Àrees temàtiques de la UPC::Física -Hydrogen -Sodium -Superfluidity -Monte Carlo method -Molecular hydrogen -two-dimensional -crystal phase of sodium -Hidrogen -Sodi -Montecarlo, Mètode de |
Derechos:
|
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/ |
Tipo de documento:
|
Artículo - Versión publicada Artículo |
Compartir:
|
|