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Title: Phase diagram of interacting bosons on the honeycomb lattice

Abstract

We study the ground-state properties of repulsively interacting bosons on the honeycomb lattice using large-scale quantum Monte Carlo simulations. In the hard-core limit, the half-filled system develops long-ranged diagonal order for sufficiently strong nearest-neighbor repulsion. This staggered solid melts at a first-order quantum phase transition into the superfluid phase, without the presence of any intermediate supersolid phase. Within the superfluid phase, both the superfluid density and the compressibility exhibit local minima near the particle (hole) density of one quarter, while the density and the condensate fraction show inflection points in this region. Relaxing the hard-core constraint, supersolid phases emerge for soft-core bosons. The suppression of the superfluid density is found to persist for sufficiently large, finite on-site repulsion.

Authors:
 [1]
  1. Institut fuer Theoretische Physik III, Universitaet Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany)
Publication Date:
OSTI Identifier:
20957831
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.75.174301; (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; 36 MATERIALS SCIENCE; BOSONS; COMPRESSIBILITY; COMPUTERIZED SIMULATION; CONDENSATES; DENSITY; GROUND STATES; HONEYCOMB STRUCTURES; INTERACTING BOSON MODEL; MONTE CARLO METHOD; PHASE DIAGRAMS; PHASE TRANSFORMATIONS; SUPERFLUIDITY

Citation Formats

Wessel, Stefan. Phase diagram of interacting bosons on the honeycomb lattice. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.174301.
Wessel, Stefan. Phase diagram of interacting bosons on the honeycomb lattice. United States. doi:10.1103/PHYSREVB.75.174301.
Wessel, Stefan. Tue . "Phase diagram of interacting bosons on the honeycomb lattice". United States. doi:10.1103/PHYSREVB.75.174301.
@article{osti_20957831,
title = {Phase diagram of interacting bosons on the honeycomb lattice},
author = {Wessel, Stefan},
abstractNote = {We study the ground-state properties of repulsively interacting bosons on the honeycomb lattice using large-scale quantum Monte Carlo simulations. In the hard-core limit, the half-filled system develops long-ranged diagonal order for sufficiently strong nearest-neighbor repulsion. This staggered solid melts at a first-order quantum phase transition into the superfluid phase, without the presence of any intermediate supersolid phase. Within the superfluid phase, both the superfluid density and the compressibility exhibit local minima near the particle (hole) density of one quarter, while the density and the condensate fraction show inflection points in this region. Relaxing the hard-core constraint, supersolid phases emerge for soft-core bosons. The suppression of the superfluid density is found to persist for sufficiently large, finite on-site repulsion.},
doi = {10.1103/PHYSREVB.75.174301},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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