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Title: Quantum Phase Transition in a Two-Dimensional System of Dipoles

Abstract

The ground-state phase diagram of a two-dimensional Bose system with dipole-dipole interactions is studied by means of a quantum Monte Carlo technique. Our calculation predicts a quantum phase transition from a gas to a solid phase when the density increases. In the gas phase, the condensate fraction is calculated as a function of the density. Using the Feynman approximation, the collective excitation branch is studied and the appearance of a roton minimum is observed. The results of the static structure factor at both sides of the gas-solid phase are also presented. The Lindemann ratio at the transition point becomes {gamma}=0.230(6). The condensate fraction in the gas phase is estimated as a function of the density.

Authors:
;  [1]; ;  [2]
  1. Departament de Fisica i Enginyeria Nuclear, Campus Nord B4-B5, Universitat Politecnica de Catalunya, E-08034 Barcelona (Spain)
  2. Institute of Spectroscopy, 142190 Troitsk (Russian Federation)
Publication Date:
OSTI Identifier:
20955436
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevLett.98.060405; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE; APPROXIMATIONS; COLLECTIVE EXCITATIONS; DIPOLES; GROUND STATES; MONTE CARLO METHOD; PHASE DIAGRAMS; PHASE TRANSFORMATIONS; STRUCTURE FACTORS; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Astrakharchik, G. E., Boronat, J., Kurbakov, I. L., and Lozovik, Yu. E. Quantum Phase Transition in a Two-Dimensional System of Dipoles. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.060405.
Astrakharchik, G. E., Boronat, J., Kurbakov, I. L., & Lozovik, Yu. E. Quantum Phase Transition in a Two-Dimensional System of Dipoles. United States. doi:10.1103/PHYSREVLETT.98.060405.
Astrakharchik, G. E., Boronat, J., Kurbakov, I. L., and Lozovik, Yu. E. Fri . "Quantum Phase Transition in a Two-Dimensional System of Dipoles". United States. doi:10.1103/PHYSREVLETT.98.060405.
@article{osti_20955436,
title = {Quantum Phase Transition in a Two-Dimensional System of Dipoles},
author = {Astrakharchik, G. E. and Boronat, J. and Kurbakov, I. L. and Lozovik, Yu. E.},
abstractNote = {The ground-state phase diagram of a two-dimensional Bose system with dipole-dipole interactions is studied by means of a quantum Monte Carlo technique. Our calculation predicts a quantum phase transition from a gas to a solid phase when the density increases. In the gas phase, the condensate fraction is calculated as a function of the density. Using the Feynman approximation, the collective excitation branch is studied and the appearance of a roton minimum is observed. The results of the static structure factor at both sides of the gas-solid phase are also presented. The Lindemann ratio at the transition point becomes {gamma}=0.230(6). The condensate fraction in the gas phase is estimated as a function of the density.},
doi = {10.1103/PHYSREVLETT.98.060405},
journal = {Physical Review Letters},
number = 6,
volume = 98,
place = {United States},
year = {Fri Feb 09 00:00:00 EST 2007},
month = {Fri Feb 09 00:00:00 EST 2007}
}
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