---
_id: '18201'
abstract:
- lang: eng
  text: Owing to thermal fluctuations, two-dimensional (2D) systems cannot undergo
    a conventional phase transition associated with the breaking of a continuous symmetry1.
    Nevertheless they may exhibit a phase transition to a state with quasi-long-range
    order via the Berezinskii–Kosterlitz–Thouless (BKT) mechanism2. A paradigm example
    is the 2D Bose fluid, such as a liquid helium film3, which cannot condense at
    non-zero temperature although it becomes superfluid above a critical phase space
    density. The quasi-long-range coherence and the microscopic nature of the BKT
    transition were recently explored with ultracold atomic gases4,5,6. However, a
    direct observation of superfluidity in terms of frictionless flow is still missing
    for these systems. Here we probe the superfluidity of a 2D trapped Bose gas using
    a moving obstacle formed by a micrometre-sized laser beam. We find a dramatic
    variation of the response of the fluid, depending on its degree of degeneracy
    at the obstacle location.
article_processing_charge: No
article_type: letter_note
arxiv: 1
author:
- first_name: Rémi
  full_name: Desbuquois, Rémi
  last_name: Desbuquois
- first_name: Lauriane
  full_name: Chomaz, Lauriane
  last_name: Chomaz
- first_name: Tarik
  full_name: Yefsah, Tarik
  last_name: Yefsah
- first_name: Julian
  full_name: Leonard, Julian
  id: b75b3f45-7995-11ef-9bfd-9a9cd02c3577
  last_name: Leonard
- first_name: Jérôme
  full_name: Beugnon, Jérôme
  last_name: Beugnon
- first_name: Christof
  full_name: Weitenberg, Christof
  last_name: Weitenberg
- first_name: Jean
  full_name: Dalibard, Jean
  last_name: Dalibard
citation:
  ama: Desbuquois R, Chomaz L, Yefsah T, et al. Superfluid behaviour of a two-dimensional
    Bose gas. <i>Nature Physics</i>. 2012;8(9):645-648. doi:<a href="https://doi.org/10.1038/nphys2378">10.1038/nphys2378</a>
  apa: Desbuquois, R., Chomaz, L., Yefsah, T., Leonard, J., Beugnon, J., Weitenberg,
    C., &#38; Dalibard, J. (2012). Superfluid behaviour of a two-dimensional Bose
    gas. <i>Nature Physics</i>. Springer Nature. <a href="https://doi.org/10.1038/nphys2378">https://doi.org/10.1038/nphys2378</a>
  chicago: Desbuquois, Rémi, Lauriane Chomaz, Tarik Yefsah, Julian Leonard, Jérôme
    Beugnon, Christof Weitenberg, and Jean Dalibard. “Superfluid Behaviour of a Two-Dimensional
    Bose Gas.” <i>Nature Physics</i>. Springer Nature, 2012. <a href="https://doi.org/10.1038/nphys2378">https://doi.org/10.1038/nphys2378</a>.
  ieee: R. Desbuquois <i>et al.</i>, “Superfluid behaviour of a two-dimensional Bose
    gas,” <i>Nature Physics</i>, vol. 8, no. 9. Springer Nature, pp. 645–648, 2012.
  ista: Desbuquois R, Chomaz L, Yefsah T, Leonard J, Beugnon J, Weitenberg C, Dalibard
    J. 2012. Superfluid behaviour of a two-dimensional Bose gas. Nature Physics. 8(9),
    645–648.
  mla: Desbuquois, Rémi, et al. “Superfluid Behaviour of a Two-Dimensional Bose Gas.”
    <i>Nature Physics</i>, vol. 8, no. 9, Springer Nature, 2012, pp. 645–48, doi:<a
    href="https://doi.org/10.1038/nphys2378">10.1038/nphys2378</a>.
  short: R. Desbuquois, L. Chomaz, T. Yefsah, J. Leonard, J. Beugnon, C. Weitenberg,
    J. Dalibard, Nature Physics 8 (2012) 645–648.
date_created: 2024-10-07T11:50:19Z
date_published: 2012-07-29T00:00:00Z
date_updated: 2024-10-07T12:05:22Z
day: '29'
doi: 10.1038/nphys2378
extern: '1'
external_id:
  arxiv:
  - '1205.4536'
intvolume: '         8'
issue: '9'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1205.4536
month: '07'
oa: 1
oa_version: Preprint
page: 645-648
publication: Nature Physics
publication_identifier:
  eissn:
  - 1745-2481
  issn:
  - 1745-2473
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Superfluid behaviour of a two-dimensional Bose gas
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 8
year: '2012'
...