Laser probing of the singleparticle energy gap of a Bose gas in an optical lattice in the Mottinsulator phase
Abstract
We study singleparticle excitations of a Bose gas in an optical lattice in the Mottinsulator phase. The characteristic feature of the singleparticle spectrum in the Mottinsulator phase is the existence of an energy gap between the particle and hole excitations. We show that the singleparticle excitation energies and associated energy gap in the Mottinsulator phase can be directly probed by an outputcoupling experiment. We apply the general expression for the output current derived by Luxat and Griffin, which is given in terms of the singleparticle Green's functions of a trapped Bose gas, to the Mottinsulator phase using the BoseHubbard model. The energy spectrum of the momentumresolved output current exhibits two characteristic peaks corresponding to the particle and hole excitations, and thus it can be used to detect the transition point from the Mott insulator to superfluid phase where the energy gap disappears.
 Authors:
 Department of Physics, Faculty of Science, Tokyo University of Science, 13 Kagurazaka, Shinjukuku, Tokyo, 1628601 (Japan)
 Department of Applied Physics, Faculty of Science, Tokyo University of Science, 13 Kagurazaka, Shinjukuku, Tokyo, 1628601 (Japan)
 Publication Date:
 OSTI Identifier:
 20786979
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.033621; (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; BOSEEINSTEIN GAS; BOSONS; COUPLING; ELECTRIC CURRENTS; ENERGY GAP; ENERGY SPECTRA; EXCITATION; GREEN FUNCTION; HOLES; HUBBARD MODEL; LASER RADIATION; RADIATION PRESSURE; SUPERFLUIDITY; TRAPPING
Citation Formats
Konabe, S., Nikuni, T., and Nakamura, M. Laser probing of the singleparticle energy gap of a Bose gas in an optical lattice in the Mottinsulator phase. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.
Konabe, S., Nikuni, T., & Nakamura, M. Laser probing of the singleparticle energy gap of a Bose gas in an optical lattice in the Mottinsulator phase. United States. doi:10.1103/PHYSREVA.73.0.
Konabe, S., Nikuni, T., and Nakamura, M. Wed .
"Laser probing of the singleparticle energy gap of a Bose gas in an optical lattice in the Mottinsulator phase". United States.
doi:10.1103/PHYSREVA.73.0.
@article{osti_20786979,
title = {Laser probing of the singleparticle energy gap of a Bose gas in an optical lattice in the Mottinsulator phase},
author = {Konabe, S. and Nikuni, T. and Nakamura, M.},
abstractNote = {We study singleparticle excitations of a Bose gas in an optical lattice in the Mottinsulator phase. The characteristic feature of the singleparticle spectrum in the Mottinsulator phase is the existence of an energy gap between the particle and hole excitations. We show that the singleparticle excitation energies and associated energy gap in the Mottinsulator phase can be directly probed by an outputcoupling experiment. We apply the general expression for the output current derived by Luxat and Griffin, which is given in terms of the singleparticle Green's functions of a trapped Bose gas, to the Mottinsulator phase using the BoseHubbard model. The energy spectrum of the momentumresolved output current exhibits two characteristic peaks corresponding to the particle and hole excitations, and thus it can be used to detect the transition point from the Mott insulator to superfluid phase where the energy gap disappears.},
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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