Excitations of One-Dimensional Bose-Einstein Condensates in a Random Potential

Journal Article · Fri Oct 24 04:00:00 EDT 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.101.170407· OSTI ID:21179833

Gurarie, V ^[1]; Refael, G ^[2]; Chalker, J T ^[3]

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1. Department of Physics, University of Colorado, Boulder Colorado 80309 (United States)
2. Department of Physics, California Institute of Technology, Pasadena California 91125 (United States)
3. Rudolf Peiers Centre for Theoretical Physics, Oxford University, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

We examine bosons hopping on a one-dimensional lattice in the presence of a random potential at zero temperature. Bogoliubov excitations of the Bose-Einstein condensate formed under such conditions are localized, with the localization length diverging at low frequency as l({omega}){approx}1/{omega}{sup {alpha}}. We show that the well-known result {alpha}=2 applies only for sufficiently weak random potential. As the random potential is increased beyond a certain strength, {alpha} starts decreasing. At a critical strength of the potential, when the system of bosons is at the transition from a superfluid to an insulator, {alpha}=1. This result is relevant for understanding the behavior of the atomic Bose-Einstein condensates in the presence of random potential, and of the disordered Josephson junction arrays.

• OSTI ID: 21179833
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 17 Vol. 101; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BOSE-EINSTEIN CONDENSATION
BOSONS
EXCITATION
JOSEPHSON JUNCTIONS
ONE-DIMENSIONAL CALCULATIONS
POTENTIALS
RANDOMNESS
SUPERFLUIDITY