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Critical flow and dissipation in a quasi–one-dimensional superfluid
In one of the most celebrated examples of the theory of universal critical phenomena, the phase transition to the superfluid state of (4)He belongs to the same three-dimensional (3D) O(2) universality class as the onset of ferromagnetism in a lattice of classical spins with XY symmetry. Below the tr...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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American Association for the Advancement of Science
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4640651/ https://www.ncbi.nlm.nih.gov/pubmed/26601177 http://dx.doi.org/10.1126/sciadv.1400222 |
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author | Duc, Pierre-François Savard, Michel Petrescu, Matei Rosenow, Bernd Del Maestro, Adrian Gervais, Guillaume |
author_facet | Duc, Pierre-François Savard, Michel Petrescu, Matei Rosenow, Bernd Del Maestro, Adrian Gervais, Guillaume |
author_sort | Duc, Pierre-François |
collection | PubMed |
description | In one of the most celebrated examples of the theory of universal critical phenomena, the phase transition to the superfluid state of (4)He belongs to the same three-dimensional (3D) O(2) universality class as the onset of ferromagnetism in a lattice of classical spins with XY symmetry. Below the transition, the superfluid density ρ(s) and superfluid velocity v(s) increase as a power law of temperature described by a universal critical exponent that is constrained to be identical by scale invariance. As the dimensionality is reduced toward 1D, it is expected that enhanced thermal and quantum fluctuations preclude long-range order, thereby inhibiting superfluidity. We have measured the flow rate of liquid helium and deduced its superfluid velocity in a capillary flow experiment occurring in single 30-nm-long nanopores with radii ranging down from 20 to 3 nm. As the pore size is reduced toward the 1D limit, we observe the following: (i) a suppression of the pressure dependence of the superfluid velocity; (ii) a temperature dependence of v(s) that surprisingly can be well-fitted by a power law with a single exponent over a broad range of temperatures; and (iii) decreasing critical velocities as a function of decreasing radius for channel sizes below R ≃ 20 nm, in stark contrast with what is observed in micrometer-sized channels. We interpret these deviations from bulk behavior as signaling the crossover to a quasi-1D state, whereby the size of a critical topological defect is cut off by the channel radius. |
format | Online Article Text |
id | pubmed-4640651 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | American Association for the Advancement of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-46406512015-11-23 Critical flow and dissipation in a quasi–one-dimensional superfluid Duc, Pierre-François Savard, Michel Petrescu, Matei Rosenow, Bernd Del Maestro, Adrian Gervais, Guillaume Sci Adv Research Articles In one of the most celebrated examples of the theory of universal critical phenomena, the phase transition to the superfluid state of (4)He belongs to the same three-dimensional (3D) O(2) universality class as the onset of ferromagnetism in a lattice of classical spins with XY symmetry. Below the transition, the superfluid density ρ(s) and superfluid velocity v(s) increase as a power law of temperature described by a universal critical exponent that is constrained to be identical by scale invariance. As the dimensionality is reduced toward 1D, it is expected that enhanced thermal and quantum fluctuations preclude long-range order, thereby inhibiting superfluidity. We have measured the flow rate of liquid helium and deduced its superfluid velocity in a capillary flow experiment occurring in single 30-nm-long nanopores with radii ranging down from 20 to 3 nm. As the pore size is reduced toward the 1D limit, we observe the following: (i) a suppression of the pressure dependence of the superfluid velocity; (ii) a temperature dependence of v(s) that surprisingly can be well-fitted by a power law with a single exponent over a broad range of temperatures; and (iii) decreasing critical velocities as a function of decreasing radius for channel sizes below R ≃ 20 nm, in stark contrast with what is observed in micrometer-sized channels. We interpret these deviations from bulk behavior as signaling the crossover to a quasi-1D state, whereby the size of a critical topological defect is cut off by the channel radius. American Association for the Advancement of Science 2015-05-15 /pmc/articles/PMC4640651/ /pubmed/26601177 http://dx.doi.org/10.1126/sciadv.1400222 Text en Copyright © 2015, The Authors http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. |
spellingShingle | Research Articles Duc, Pierre-François Savard, Michel Petrescu, Matei Rosenow, Bernd Del Maestro, Adrian Gervais, Guillaume Critical flow and dissipation in a quasi–one-dimensional superfluid |
title | Critical flow and dissipation in a quasi–one-dimensional superfluid |
title_full | Critical flow and dissipation in a quasi–one-dimensional superfluid |
title_fullStr | Critical flow and dissipation in a quasi–one-dimensional superfluid |
title_full_unstemmed | Critical flow and dissipation in a quasi–one-dimensional superfluid |
title_short | Critical flow and dissipation in a quasi–one-dimensional superfluid |
title_sort | critical flow and dissipation in a quasi–one-dimensional superfluid |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4640651/ https://www.ncbi.nlm.nih.gov/pubmed/26601177 http://dx.doi.org/10.1126/sciadv.1400222 |
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