Observation of a spinning top in a Bose-Einstein condensate
Authors: Bisset R.N., Serafini S., Iseni E., Barbiero M., Bienaimé T., Lamporesi G., Ferrari G., Dalfovo F.
Autors Affiliation: 1 INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, 38123 Povo, Italy
2 Politecnico di Torino, Dipartimento di Elettronica e Telecomunicazioni, Corso Duca degli Abruzzi 24, 10129 Torino, Italy
Abstract: Boundaries strongly affect the behavior of quantized vortices in Bose-Einstein condensates, a phenomenon particularly evident in elongated cigar-shaped traps where vortices tend to orient along a short direction to minimize energy. Remarkably, contributions to the angular momentum of these vortices are tightly confined to the region surrounding the core, in stark contrast to untrapped condensates where all atoms contribute h ̄. We develop a theoretical model and use this, in combination with numerical simulations, to show that such localized vortices precess in a manner analogous to that of a classical spinning top. We experimentally verify this spinning-top behavior with our real-time imaging technique that allows for the tracking of position and orientation of vortices as they dynamically evolve. Finally, we perform an in-depth numerical investigation of our real-time expansion and imaging method, with the aim of guiding future experimental implementation as well as outlining directions for its improvement.
Journal/Review: PHYSICAL REVIEW A
Volume: 96 Pages from: 053605-1 to: 053605-10