Dynamic response of onedimensional bosons in a trap
Abstract
We calculate the dynamic structure factor S(q,{omega}) of a onedimensional (1D) interacting Bose gas confined in a harmonic trap. The effective interaction depends on the strength of the confinement enforcing the (1D) motion of atoms; interaction may be further enhanced by superimposing an optical lattice on the trap potential. In the compressible state, we find that the smooth variation in the gas density around the trap center leads to softening of the singular behavior of S(q,{omega}) at the first Lieb excitation mode compared to the behavior predicted for homogeneous 1D systems. Nevertheless, the densityaveraged response S(q,{omega}) remains a nonanalytic function of q and {omega} at the first Lieb excitation mode in the limit of weak trap confinement. The exponent of the powerlaw nonanalyticity is modified due to the inhomogeneity in a universal way and thus bears unambiguously the information about the (homogeneous) LiebLiniger model. A strong optical lattice causes formation of Mott phases. Deep in the Mott regime, we predict a semicircular peak in S(q,{omega}) centered at the onsite repulsion energy, {omega}=U. Similar peaks of smaller amplitudes exist at multiples of U as well. We explain the suppression of the dynamic response with entering into the Mott regime, observed recentlymore »
 Authors:
 Physics Department, Arnold Sommerfeld Center for Theoretical Physics, and Center for NanoScience, LudwigMaximiliansUniversitaet, 80333 Munich (Germany)
 Laboratoire de Physique et de Modelisation des Milieux Condenses, C.N.R.S., Universite Joseph Fourier, BP 166, 38042 Grenoble (France)
 Department of Physics, Yale University, New Haven, Connecticut 06520 (United States)
 Publication Date:
 OSTI Identifier:
 21316448
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 80; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.80.043611; (c) 2009 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; ATOMS; BOSEEINSTEIN GAS; BOSONS; EXCITATION; INTERACTIONS; ONEDIMENSIONAL CALCULATIONS; STRUCTURE FACTORS; SUM RULES; TRAPS
Citation Formats
Golovach, Vitaly N., Minguzzi, Anna, and Glazman, Leonid I.. Dynamic response of onedimensional bosons in a trap. United States: N. p., 2009.
Web. doi:10.1103/PHYSREVA.80.043611.
Golovach, Vitaly N., Minguzzi, Anna, & Glazman, Leonid I.. Dynamic response of onedimensional bosons in a trap. United States. doi:10.1103/PHYSREVA.80.043611.
Golovach, Vitaly N., Minguzzi, Anna, and Glazman, Leonid I.. 2009.
"Dynamic response of onedimensional bosons in a trap". United States.
doi:10.1103/PHYSREVA.80.043611.
@article{osti_21316448,
title = {Dynamic response of onedimensional bosons in a trap},
author = {Golovach, Vitaly N. and Minguzzi, Anna and Glazman, Leonid I.},
abstractNote = {We calculate the dynamic structure factor S(q,{omega}) of a onedimensional (1D) interacting Bose gas confined in a harmonic trap. The effective interaction depends on the strength of the confinement enforcing the (1D) motion of atoms; interaction may be further enhanced by superimposing an optical lattice on the trap potential. In the compressible state, we find that the smooth variation in the gas density around the trap center leads to softening of the singular behavior of S(q,{omega}) at the first Lieb excitation mode compared to the behavior predicted for homogeneous 1D systems. Nevertheless, the densityaveraged response S(q,{omega}) remains a nonanalytic function of q and {omega} at the first Lieb excitation mode in the limit of weak trap confinement. The exponent of the powerlaw nonanalyticity is modified due to the inhomogeneity in a universal way and thus bears unambiguously the information about the (homogeneous) LiebLiniger model. A strong optical lattice causes formation of Mott phases. Deep in the Mott regime, we predict a semicircular peak in S(q,{omega}) centered at the onsite repulsion energy, {omega}=U. Similar peaks of smaller amplitudes exist at multiples of U as well. We explain the suppression of the dynamic response with entering into the Mott regime, observed recently by Clement et al. [Phys. Rev. Lett. 102, 155301 (2009)], based on an fsum rule for the BoseHubbard model.},
doi = {10.1103/PHYSREVA.80.043611},
journal = {Physical Review. A},
number = 4,
volume = 80,
place = {United States},
year = 2009,
month =
}

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