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SEARCH FOR A SUPERFLUID PHASE OF PARAHYDROGEN: EXPLORING THE EFFECT OF CONFINEMENT

  • Author / Creator
    Omiyinka, Tokunbo P
  • The first part of this thesis theoretically studies the low temperature physics of parahydrogen (p-H2) confined in cylindrical channels of diameter of the order of 1 nm, based on the Continuous-Space Worm Algorithm quantum Monte Carlo simulations. On varying the attractive strength of the wall of the cylindrical pore, as well as its diameter, the equilibrium phase evolves from a single quasi-one-dimensional (1D) channel along the axis, to a concentric cylindrical shell. It is found that the quasi-1D system retains a strong propensity to crystallization, even though on weakly attractive substrates quantum fluctuations reduce somewhat such a tendency compared to the purely 1D system. No evidence of a topologically protected superfluid phase (in the Luttinger sense) is observed. Secondly, this research work explores the possibility of existence of a metastable superfluid phase of p-H2 in the low temperature limit. It was found that any possible occurence of superfluidity in supercooled p-H2 would have to be at a much lower temperature than 2 K. Furthermore, this thesis investigates how different p-H2 is from a Bose system that possesses a metastable superfluid phase despite having a crystalline ground state. Finally, study is also carried out to elucidate the inherent distinctions between an hypothetical metastable p-H2 liquid and a metastable 4He liquid, underscoring the essential origin of the almost conclusive absence of superfluidity in any phase of p-H2. Extensive discussions are also provided on the implications of this work for the possible existence of a bulk superfluid phase of parahydrogen.

  • Subjects / Keywords
  • Graduation date
    2016-06:Fall 2016
  • Type of Item
    Thesis
  • Degree
    Doctor of Philosophy
  • DOI
    https://doi.org/10.7939/R3HH6CH07
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
    English
  • Institution
    University of Alberta
  • Degree level
    Doctoral
  • Department
    • Department of Physics
  • Supervisor / co-supervisor and their department(s)
    • Professor Massimo Boninsegni, Department of Physics (Computational and Theoretical Condensed Matter)
  • Examining committee members and their departments
    • Professor Jan Jung, Department of Physics (Experimental Condensed Matter)
    • Professor Claire Currie, Department of Physics (Geophysics)
    • Professor Wolfgang Jaeger, Department of Chemistry
    • Professor Kim Chow, Department of Physics (Experimental Condensed Matter)
    • Professor Milton W. Cole (External Reader) , Penn State Department of Physics (Theoretical and Computational Condensed Matter)