{"quality_controlled":"1","oa":1,"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."}],"title":"Superfluid behaviour of a two-dimensional Bose gas","scopus_import":"1","article_type":"letter_note","doi":"10.1038/nphys2378","status":"public","oa_version":"Preprint","extern":"1","publication_status":"published","citation":{"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.","short":"R. Desbuquois, L. Chomaz, T. Yefsah, J. Leonard, J. Beugnon, C. Weitenberg, J. Dalibard, Nature Physics 8 (2012) 645–648.","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>.","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>","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>.","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."},"external_id":{"arxiv":["1205.4536"]},"intvolume":"         8","language":[{"iso":"eng"}],"type":"journal_article","publication":"Nature Physics","month":"07","issue":"9","page":"645-648","publisher":"Springer Nature","date_created":"2024-10-07T11:50:19Z","volume":8,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","_id":"18201","date_published":"2012-07-29T00:00:00Z","article_processing_charge":"No","publication_identifier":{"eissn":["1745-2481"],"issn":["1745-2473"]},"author":[{"full_name":"Desbuquois, Rémi","first_name":"Rémi","last_name":"Desbuquois"},{"last_name":"Chomaz","full_name":"Chomaz, Lauriane","first_name":"Lauriane"},{"last_name":"Yefsah","first_name":"Tarik","full_name":"Yefsah, Tarik"},{"id":"b75b3f45-7995-11ef-9bfd-9a9cd02c3577","first_name":"Julian","full_name":"Leonard, Julian","last_name":"Leonard"},{"last_name":"Beugnon","full_name":"Beugnon, Jérôme","first_name":"Jérôme"},{"last_name":"Weitenberg","full_name":"Weitenberg, Christof","first_name":"Christof"},{"last_name":"Dalibard","full_name":"Dalibard, Jean","first_name":"Jean"}],"date_updated":"2024-10-07T12:05:22Z","year":"2012","day":"29","main_file_link":[{"url":"https://arxiv.org/abs/1205.4536","open_access":"1"}]}