Topological superfluid transition in bubble-trapped condensates

Year: 2022

Authors: Tononi A., Pelster A., Salasnich L.

Autors Affiliation: Dipartimento di Fisica e Astronomia “Galileo Galilei,” Universita di Padova, via Marzolo 8, 35131 Padova, Italy; Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy; University Paris-Saclay, CNRS, LPTMS, 91405 Orsay, France; Physics Department and Research Center OPTIMAS, Technische Universitdt Kaiserslautern,nErwin-Schrtzdinger StraYAe 46, 67663 Kaiserslautern, Germany; Istituto Nazionale di Ottica (INO) del Consiglio Nazionale delle Ricerche (CNR), via Nello Carrara 1, 50125 Sesto Fiorentino, Italy; Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy

Abstract: Ultracold quantum gases are highly controllable and thus capable of simulating difficult quantum many-body problems ranging from condensed matter physics to astrophysics. Although experimental realizations have so far been restricted to flat geometries, recently also curved quantum systems, with the prospect of exploring tunable geometries, have been produced in microgravity facilities as ground-based experiments are technically limited. Here, we analyze bubble-trapped condensates, in which the atoms are confined on the surface of a thin spherically symmetric shell by means of external magnetic fields. A thermally induced proliferation of vorticity yields a vanishing of superfluidity. We describe the occurrence of this topological transition by conceptually extending the theory of Berezinskii, Kosterlitz, and Thouless for infinite uniform systems to such finite-size systems. Unexpectedly, we find universal scaling relations for the mean critical temperature and the finite width of the superfluid transition. Furthermore, we elucidate how they could be experimentally observed in finiteerature hydrodynamic excitations.

Journal/Review: PHYSICAL REVIEW RESEARCH

Volume: 4 (1)      Pages from: 013122-1  to: 013122-8

More Information: The authors acknowledge useful discussions with A. Fetter, T.-L. Ho, N. Lundblad, and D. R. Nelson. A.P. acknowledges financial support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) via the Collaborative Research Center SFB/TR185 (Project No. 277625399). A.T. acknowledges the support of the ANR grant Droplets (19CE30-0003).
KeyWords: PHASE-TRANSITION; VORTICES; DENSITY; PHYSICS; HELIUM; FILMS
DOI: 10.1103/PhysRevResearch.4.013122