Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Europhysics Letters (EPL)

Strongly Correlated Bosons on a Lattice: A Slave-Boson Approach

K. Ziegler

Published Sep 1, 1993• 16 citations
Publisher

Abstract

The grand canonical system of hard-core bosons, subject to thermal fluctuations, is studied on a lattice. Starting from the slave-boson representation we derive an effective Ginzburg-Landau functional for the superfluid order parameter. The order parameter field is a collective field constructed from the slave-boson fields for empty and singly occupied sites. We find two phase transitions; one from a normal fluid at high density to a superfluid and another one from the superfluid to a normal fluid at low density.

DOI
10.1209/0295-5075/23/7/001

Related papers

Condensation of a hard-core Bose gas

K. Ziegler

A grand canonical system of hard-core bosons, subject to thermal fluctuations, is studied on a lattice. Starting from the slave-boson representation with fields for occupied and unoccupied sites, an effective field theory is derived in which a complex field corresponds with the order parameter of the condensate and a real field with the total density of bosons. Near the boundary between the normal and the superfluid phase, we obtain the Ginzburg-Landau functional for the superfluid order parameter. A mean-field calculation shows that the critical temperature ${T}_{c}$ increases with increasing density up to a maximum and decreases with further increasing density.

arXiv:cond-mat/0001074•Physical Review A•Jul 20, 2000•9 citations

Thet-Jmodel of hard-core bosons in slave-particle representation and its Monte-Carlo simulations

Yuki Nakano, Takumi Ishima, Naohiro Kobayashi +3 more

We study the system of hard-core bosons (HCB) with two species in the three-dimensional lattice at finite temperatures. In the strong-correlation limit, the system becomes the t-J model, that is, the t-J model of bosonic electrons. The electron operator Bxσ at the site x with a two-component spin σ(= 1, 2***) is treated as a HCB operator, and represented by a composite of two slave particles; a spinon described by a Schwinger boson (CP1 boson) zxσ and a holon described by a HCB field x as Bxσ = †xzxσ.*** This x is again represented by another CP1 quasi-spinon operator ωxa*** (a = 1, 2***). The phase diagrams of the resulting double CP1 system obtained by Monte Carlo simulations involve first-order and second-order phase boundaries. We present in detail the techniques and algorithm to reduce the hysteresis and locate the first-order transition points.

Journal of Physics Conference Series•Dec 17, 2012•1 citation

Functional Integration in Bose Systems with Hard-Core Interaction

K. Ziegler

A grand canonical ensemble of interacting bosons is considered. The zero temperature phase diagram is evaluated from the mean-field approximation of the functional integral. Three phases are found: a superfluid, a normal fluid and a Mott insulator.

arXiv:cond-mat/9608017•Aug 5, 1996•0 citations

Phase transitions in Bose-Fermi-Hubbard model in the heavy fermion limit: Hard-core boson approach

Stasyuk, Володимир Олександрович Краснов

Phase transitions are investigated in the Bose-Fermi-Hubbard model in the mean field and hard-core boson approximations for the case of infinitely small fermion transfer and repulsive on-site boson-fermion interaction.The behavior of the Bose-Einstein condensate order parameter and grand canonical potential is analyzed as functions of the chemical potential of bosons at zero temperature.The possibility of change of order of the phase transition to the superfluid phase in the regime of fixed values of the chemical potentials of Bose-and Fermi-particles is established.The relevant phase diagrams are built.

arXiv:1512.07798•Condensed Matter Physics•Dec 1, 2015•10 citations

Slave Boson Formulation for Interacting Boson Systems and the Superfluid-Insulator Transition

Raymond Frésard

A new formulation for the study of interacting bosons on a lattice is introduced. This approach is used to give analytical expressions for the Mott insulating lobes in the phase diagram and to calculate the density-density correlation function. It is also shown that, at mean-field level, this newly introduced slave boson theory coincides with mean-field theory of a suitably introduced order parameter.

arXiv:cond-mat/9405053•May 20, 1994•1 citation

Properties of a Dense Bose–Einstein Condensate

K. Ziegler

A grand canonical ensemble of hard-core bosons is considered, subject to thermal fluctuations. We derive a two-fluid theory for this system in which the normal component interacts with the condensate. The latter is described by a complex order parameter field Φ and the total density by a real field φ. The interaction of the condensed and the noncondensed bosons leads to depletion of the condensate. This effect is discussed in a homogeneous and in a trapped Bose gas.

•Jan 1, 2002•0 citations
The grand canonical system of hard-core bosons, subject to thermal fluctuations, is studied on a lattice. Starting from the slave-boson representation we derive an effective Ginzburg-Landau functional for the superfluid order parameter. The order parameter field is a collective field constructed from the slave-boson fields for empty and singly occupied sites. We find two phase transitions; one from a normal fluid at high density to a superfluid and another one from the superfluid to a normal fluid at low density.
A grand canonical system of hard-core bosons, subject to thermal fluctuations, is studied on a lattice. Starting from the slave-boson representation with fields for occupied and unoccupied sites, an effective field theory is derived in which a complex field corresponds with the order parameter of the condensate and a real field with the total density of bosons. Near the boundary between the normal and the superfluid phase, we obtain the Ginzburg-Landau functional for the superfluid order parameter. A mean-field calculation shows that the critical temperature Tc{T}_{c}Tc​ increases with increasing density up to a maximum and decreases with further increasing density.
We study the system of hard-core bosons (HCB) with two species in the three-dimensional lattice at finite temperatures. In the strong-correlation limit, the system becomes the t-J model, that is, the t-J model of bosonic electrons. The electron operator Bxσ at the site x with a two-component spin σ(= 1, 2***) is treated as a HCB operator, and represented by a composite of two slave particles; a spinon described by a Schwinger boson (CP1 boson) zxσ and a holon described by a HCB field x as Bxσ = †xzxσ.*** This x is again represented by another CP1 quasi-spinon operator ωxa*** (a = 1, 2***). The phase diagrams of the resulting double CP1 system obtained by Monte Carlo simulations involve first-order and second-order phase boundaries. We present in detail the techniques and algorithm to reduce the hysteresis and locate the first-order transition points.
Phase transitions are investigated in the Bose-Fermi-Hubbard model in the mean field and hard-core boson approximations for the case of infinitely small fermion transfer and repulsive on-site boson-fermion interaction.The behavior of the Bose-Einstein condensate order parameter and grand canonical potential is analyzed as functions of the chemical potential of bosons at zero temperature.The possibility of change of order of the phase transition to the superfluid phase in the regime of fixed values of the chemical potentials of Bose-and Fermi-particles is established.The relevant phase diagrams are built.