One dimensional behavior of superfluid helium

Open Access
Author:
Banavar, Samhita Prarthana
Area of Honors:
Physics
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Moses Hung Wai Chan, Thesis Supervisor
  • Richard Wallace Robinett, Honors Advisor
Keywords:
  • superfluid
  • helium
  • Josephson
  • quantum mechanics
  • dimension
Abstract:
In truly one-dimensional systems, superconductivity and superfluidity are destroyed at any nonzero temperature due to phase fluctuations. This 1D confinement effect in superconductors has been studied through the behavior of metal nanowires. Here we report the results of analogous experimental studies of superfluidity in quasi-one dimensional geometries realized with glass fibers with long and narrow open channels. The flow of liquid helium through glass fibers at temperatures below 4 K was measured with a quartz crystal microbalance and a mass spectrometer. An abrupt increase of the flow rate at low temperatures was observed in two glass fibers of 1 m length – 1.7 μm diameter and 4 cm length – 150 nm diameters respectively. This preliminary result suggests the existence of superfluidity in quasi-1D systems with aspect ratio as high as 6×105. The effects of the 1D confinement will be discussed.