Superfluidity of metastable glassy bulk para -hydrogen at low temperature

• Published in: Physical review. B, Condensed matter and materials physics Vol. 85; no. 22
• Main Authors: Osychenko, O. N., Rota, R., Boronat, J.
• Format: Journal Article Publication
• Language: English
• Published: 13-06-2012
• Subjects: Computer simulation; Condensed matter; Density; Fluids; Física; Física de fluids; Liquid phases; Monte Carlo methods; Superconductivitat; Superconductivity; Superfluidity; Superfluïdesa; Temperature dependence; Àrees temàtiques de la UPC
• ISSN: 1098-0121; 1550-235X
• DOI: 10.1103/PhysRevB.85.224513

Molecular para-hydrogen (p-H sub(2)) has been proposed theoretically as a possible candidate for superfluidity, but the eventual superfluid transition is hindered by its crystallization. In this work, we study a metastable noncrystalline phase of bulk p-H sub(2) by means of the path integral Monte Carlo method in order to investigate at which temperature this system can support superfluidity. By choosing accurately the initial configuration and using a noncommensurate simulation box, we have been able to frustrate the formation of the crystal in the simulated system and to calculate the temperature dependence of the one-body density matrix and of the superfluid fraction. We observe a transition to a superfluid phase at temperatures around 1 K. The limit of zero temperature is also studied using the diffusion Monte Carlo method. Results for the energy, condensate fraction, and structure of the metastable liquid phase at T = 0 are reported and compared with the ones obtained for the stable solid phase.