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Title: Nematic Order by Disorder in Spin-2 Bose-Einstein Condensates

Abstract

We show that quantum and thermal fluctuations in spin-2 Bose-Einstein condensates lift the accidental degeneracy of the mean-field phase diagram. Fluctuations select the uniaxial (square biaxial) nematic state for scattering lengths a{sub 4}>a{sub 2} (a{sub 4}<a{sub 2}). Paradoxically, the order is stronger at higher temperatures. For spin-2 {sup 87}Rb and {sup 23}Na, a continuous Ising-type transition is predicted on raising the magnetic field, from a fluctuation stabilized uniaxial state to a field stabilized square biaxial order state. This is a promising experimental system to realize the ''order-by-disorder'' phenomenon.

Authors:
;  [1];  [2];  [3]
  1. Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)
  2. Department of Physics, California Institute of Technology, MC 114-36, Pasadena, California 91125 (United States)
  3. Department of Physics, University of California, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
20951348
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevLett.98.190404; (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; FLUCTUATIONS; MAGNETIC FIELDS; MEAN-FIELD THEORY; PHASE DIAGRAMS; RUBIDIUM 87; SCATTERING LENGTHS; SODIUM 23; SPIN

Citation Formats

Turner, Ari M., Demler, Eugene, Barnett, Ryan, and Vishwanath, Ashvin. Nematic Order by Disorder in Spin-2 Bose-Einstein Condensates. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.190404.
Turner, Ari M., Demler, Eugene, Barnett, Ryan, & Vishwanath, Ashvin. Nematic Order by Disorder in Spin-2 Bose-Einstein Condensates. United States. doi:10.1103/PHYSREVLETT.98.190404.
Turner, Ari M., Demler, Eugene, Barnett, Ryan, and Vishwanath, Ashvin. Fri . "Nematic Order by Disorder in Spin-2 Bose-Einstein Condensates". United States. doi:10.1103/PHYSREVLETT.98.190404.
@article{osti_20951348,
title = {Nematic Order by Disorder in Spin-2 Bose-Einstein Condensates},
author = {Turner, Ari M. and Demler, Eugene and Barnett, Ryan and Vishwanath, Ashvin},
abstractNote = {We show that quantum and thermal fluctuations in spin-2 Bose-Einstein condensates lift the accidental degeneracy of the mean-field phase diagram. Fluctuations select the uniaxial (square biaxial) nematic state for scattering lengths a{sub 4}>a{sub 2} (a{sub 4}<a{sub 2}). Paradoxically, the order is stronger at higher temperatures. For spin-2 {sup 87}Rb and {sup 23}Na, a continuous Ising-type transition is predicted on raising the magnetic field, from a fluctuation stabilized uniaxial state to a field stabilized square biaxial order state. This is a promising experimental system to realize the ''order-by-disorder'' phenomenon.},
doi = {10.1103/PHYSREVLETT.98.190404},
journal = {Physical Review Letters},
number = 19,
volume = 98,
place = {United States},
year = {Fri May 11 00:00:00 EDT 2007},
month = {Fri May 11 00:00:00 EDT 2007}
}
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