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Title: Radial and Angular Rotons in Trapped Dipolar Gases

Abstract

We study Bose-Einstein condensates with purely dipolar interactions in oblate traps. We find that the condensate always becomes unstable to collapse when the number of particles is sufficiently large. We analyze the instability, and find that it is the trapped-gas analogue of the 'roton-maxon' instability previously reported for a gas that is unconfined in 2D. In addition, we find that under certain circumstances the condensate wave function attains a biconcave shape, with its maximum density away from the center of the gas. These biconcave condensates become unstable due to azimuthal excitation--an angular roton.

Authors:
; ;  [1];  [2];  [3];  [2]
  1. JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440 (United States)
  2. (United States)
  3. (Italy)
Publication Date:
OSTI Identifier:
20861610
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevLett.98.030406; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSE-EINSTEIN CONDENSATION; EXCITATION; GASES; INSTABILITY; TRAPPING; TRAPS; WAVE FUNCTIONS

Citation Formats

Ronen, Shai, Bortolotti, Daniele C. E., Bohn, John L., JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, and LENS and Dipartimento di Fisica, Universita di Firenze, Sesto Fiorentino, and JILA, NIST, and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440. Radial and Angular Rotons in Trapped Dipolar Gases. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.030406.
Ronen, Shai, Bortolotti, Daniele C. E., Bohn, John L., JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, and LENS and Dipartimento di Fisica, Universita di Firenze, Sesto Fiorentino, & JILA, NIST, and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440. Radial and Angular Rotons in Trapped Dipolar Gases. United States. doi:10.1103/PHYSREVLETT.98.030406.
Ronen, Shai, Bortolotti, Daniele C. E., Bohn, John L., JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, and LENS and Dipartimento di Fisica, Universita di Firenze, Sesto Fiorentino, and JILA, NIST, and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440. Fri . "Radial and Angular Rotons in Trapped Dipolar Gases". United States. doi:10.1103/PHYSREVLETT.98.030406.
@article{osti_20861610,
title = {Radial and Angular Rotons in Trapped Dipolar Gases},
author = {Ronen, Shai and Bortolotti, Daniele C. E. and Bohn, John L. and JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440 and and LENS and Dipartimento di Fisica, Universita di Firenze, Sesto Fiorentino and JILA, NIST, and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440},
abstractNote = {We study Bose-Einstein condensates with purely dipolar interactions in oblate traps. We find that the condensate always becomes unstable to collapse when the number of particles is sufficiently large. We analyze the instability, and find that it is the trapped-gas analogue of the 'roton-maxon' instability previously reported for a gas that is unconfined in 2D. In addition, we find that under certain circumstances the condensate wave function attains a biconcave shape, with its maximum density away from the center of the gas. These biconcave condensates become unstable due to azimuthal excitation--an angular roton.},
doi = {10.1103/PHYSREVLETT.98.030406},
journal = {Physical Review Letters},
number = 3,
volume = 98,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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