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Title: Ground state of hard-core bosons in one-dimensional periodic potentials

Abstract

With Girardeau's Fermi-Bose mapping, we find the exact ground states of hard-core bosons residing in a one-dimensional periodic potential. The analysis of these ground states shows that when the number of bosons N is commensurate with the number of wells M in the periodic potential, the boson system is a Mott insulator whose energy gap, however, is given by the single-particle band gap of the periodic potential; when N is not commensurate with M, the system is a metal (not a superfluid). In fact, we argue that there may be no superfluid phase for any one-dimensional boson system in terms of Landau's criterion of superfluidity. The Kronig-Penney potential is used to illustrate our results.

Authors:
;  [1]
  1. Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)
Publication Date:
OSTI Identifier:
20982164
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023613; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BOSONS; ENERGY GAP; FERMIONS; GROUND STATES; METALS; ONE-DIMENSIONAL CALCULATIONS; PARTICLES; PERIODICITY; POTENTIALS; SUPERFLUIDITY

Citation Formats

Lin, Yuan, and Wu, Biao. Ground state of hard-core bosons in one-dimensional periodic potentials. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.023613.
Lin, Yuan, & Wu, Biao. Ground state of hard-core bosons in one-dimensional periodic potentials. United States. doi:10.1103/PHYSREVA.75.023613.
Lin, Yuan, and Wu, Biao. Thu . "Ground state of hard-core bosons in one-dimensional periodic potentials". United States. doi:10.1103/PHYSREVA.75.023613.
@article{osti_20982164,
title = {Ground state of hard-core bosons in one-dimensional periodic potentials},
author = {Lin, Yuan and Wu, Biao},
abstractNote = {With Girardeau's Fermi-Bose mapping, we find the exact ground states of hard-core bosons residing in a one-dimensional periodic potential. The analysis of these ground states shows that when the number of bosons N is commensurate with the number of wells M in the periodic potential, the boson system is a Mott insulator whose energy gap, however, is given by the single-particle band gap of the periodic potential; when N is not commensurate with M, the system is a metal (not a superfluid). In fact, we argue that there may be no superfluid phase for any one-dimensional boson system in terms of Landau's criterion of superfluidity. The Kronig-Penney potential is used to illustrate our results.},
doi = {10.1103/PHYSREVA.75.023613},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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