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Title: Engineering vortex rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates

Abstract

We study controlled methods of preparing vortex configurations in atomic Bose-Einstein condensates and their use in the studies of fundamental vortex scattering, reconnection processes, and superfluid sound emission. We explore techniques of imprinting vortex rings by means of coherently driving internal atomic transitions with electromagnetic fields which exhibit singular phase profiles. In particular, we show that a vortex ring can be prepared by two focused co-propagating Gaussian laser beams. More complex vortex systems may also be imprinted by directly superposing simpler field configurations or by programming their phase profiles on optical holograms. We analyze specific examples of two merging vortex rings in a trapped two-species {sup 87}Rb gas. We calculate the radiated sound energy in the reconnection process and show that the vortex relaxation and the redistribution of sound energy can be controlled by the imprinting process. As another creation technique, we study engineering pairs of two-dimensional point vortices in the condensates using a 'light roadblock' in ultraslow light propagation. We show how this can be used to study vortex collisions in compressible superfluids and how these collisions result in energy dissipation via phonons and, sometimes, annihilation of vortex pairs.

Authors:
 [1];  [2];  [3]
  1. School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom)
  2. (United Kingdom)
  3. Naval Research Laboratory, Washington, DC 20375 (United States)
Publication Date:
OSTI Identifier:
20786363
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.063626; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANNIHILATION; BOSE-EINSTEIN CONDENSATION; ELECTROMAGNETIC FIELDS; ENERGY LOSSES; HOLOGRAPHY; LASER RADIATION; LIGHT TRANSMISSION; PHONONS; PHOTON-ATOM COLLISIONS; RELAXATION; RUBIDIUM; RUBIDIUM 87; SCATTERING; SOUND WAVES; SUPERFLUIDITY; TRAPPING; TWO-DIMENSIONAL CALCULATIONS; VISIBLE RADIATION; VORTICES

Citation Formats

Ruostekoski, Janne, Department of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, Herts AL10 9AB, and Dutton, Zachary. Engineering vortex rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Ruostekoski, Janne, Department of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, Herts AL10 9AB, & Dutton, Zachary. Engineering vortex rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates. United States. doi:10.1103/PHYSREVA.72.0.
Ruostekoski, Janne, Department of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, Herts AL10 9AB, and Dutton, Zachary. Thu . "Engineering vortex rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786363,
title = {Engineering vortex rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates},
author = {Ruostekoski, Janne and Department of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, Herts AL10 9AB and Dutton, Zachary},
abstractNote = {We study controlled methods of preparing vortex configurations in atomic Bose-Einstein condensates and their use in the studies of fundamental vortex scattering, reconnection processes, and superfluid sound emission. We explore techniques of imprinting vortex rings by means of coherently driving internal atomic transitions with electromagnetic fields which exhibit singular phase profiles. In particular, we show that a vortex ring can be prepared by two focused co-propagating Gaussian laser beams. More complex vortex systems may also be imprinted by directly superposing simpler field configurations or by programming their phase profiles on optical holograms. We analyze specific examples of two merging vortex rings in a trapped two-species {sup 87}Rb gas. We calculate the radiated sound energy in the reconnection process and show that the vortex relaxation and the redistribution of sound energy can be controlled by the imprinting process. As another creation technique, we study engineering pairs of two-dimensional point vortices in the condensates using a 'light roadblock' in ultraslow light propagation. We show how this can be used to study vortex collisions in compressible superfluids and how these collisions result in energy dissipation via phonons and, sometimes, annihilation of vortex pairs.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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