Phase diagram of interacting bosons on the honeycomb lattice
Abstract
We study the groundstate properties of repulsively interacting bosons on the honeycomb lattice using largescale quantum Monte Carlo simulations. In the hardcore limit, the halffilled system develops longranged diagonal order for sufficiently strong nearestneighbor repulsion. This staggered solid melts at a firstorder 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 hardcore constraint, supersolid phases emerge for softcore bosons. The suppression of the superfluid density is found to persist for sufficiently large, finite onsite repulsion.
 Authors:
 Institut fuer Theoretische Physik III, Universitaet Stuttgart, Pfaffenwaldring 57, D70550 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 groundstate properties of repulsively interacting bosons on the honeycomb lattice using largescale quantum Monte Carlo simulations. In the hardcore limit, the halffilled system develops longranged diagonal order for sufficiently strong nearestneighbor repulsion. This staggered solid melts at a firstorder 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 hardcore constraint, supersolid phases emerge for softcore bosons. The suppression of the superfluid density is found to persist for sufficiently large, finite onsite 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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