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Title: Itinerant-localized dual character of a strongly correlated superfluid Bose gas in an optical lattice

Abstract

We investigate a strongly correlated Bose gas in an optical lattice. Extending the standard-basis operator method developed by Haley and Erdoes to a boson Hubbard model, we calculate excitation spectra in the superfluid phase, as well as in the Mott insulating phase, at T=0. In the Mott phase, the excitation spectrum has a finite energy gap, reflecting the localized character of atoms. In the superfluid phase, the excitation spectrum is shown to have an itinerant-localized dual structure, where the gapless Bogoliubov mode (which describes the itinerant character of superfluid atoms) and a band with a finite energy gap coexist. We also show that the rf-tunneling current measurement would give useful information about the duality of a strongly correlated superfluid Bose gas near the superfluid-insulator transition.

Authors:
; ;  [1]
  1. Institute of Physics, University of Tsukuba, Tsukuba, Ibaraki 305 (Japan)
Publication Date:
OSTI Identifier:
20786975
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.033617; (c) 2006 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; ABSORPTION SPECTRA; ATOMS; BOSE-EINSTEIN GAS; BOSONS; DUALITY; ENERGY GAP; EXCITATION; HUBBARD MODEL; SUPERFLUIDITY; TUNNEL EFFECT

Citation Formats

Ohashi, Y., Kitaura, M., and Matsumoto, H. Itinerant-localized dual character of a strongly correlated superfluid Bose gas in an optical lattice. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Ohashi, Y., Kitaura, M., & Matsumoto, H. Itinerant-localized dual character of a strongly correlated superfluid Bose gas in an optical lattice. United States. doi:10.1103/PHYSREVA.73.0.
Ohashi, Y., Kitaura, M., and Matsumoto, H. Wed . "Itinerant-localized dual character of a strongly correlated superfluid Bose gas in an optical lattice". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786975,
title = {Itinerant-localized dual character of a strongly correlated superfluid Bose gas in an optical lattice},
author = {Ohashi, Y. and Kitaura, M. and Matsumoto, H.},
abstractNote = {We investigate a strongly correlated Bose gas in an optical lattice. Extending the standard-basis operator method developed by Haley and Erdoes to a boson Hubbard model, we calculate excitation spectra in the superfluid phase, as well as in the Mott insulating phase, at T=0. In the Mott phase, the excitation spectrum has a finite energy gap, reflecting the localized character of atoms. In the superfluid phase, the excitation spectrum is shown to have an itinerant-localized dual structure, where the gapless Bogoliubov mode (which describes the itinerant character of superfluid atoms) and a band with a finite energy gap coexist. We also show that the rf-tunneling current measurement would give useful information about the duality of a strongly correlated superfluid Bose gas near the superfluid-insulator transition.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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