Symmetry breaking in the Hubbard model at zero temperature

1993 ◽  
Vol 47 (5) ◽  
pp. 2901-2904
Author(s):  
Gang Su
Keyword(s):  
Symmetry Breaking ◽  
Hubbard Model ◽  
Zero Temperature

scholarly journals Symmetry-breaking topological insulators in the Z2 Bose-Hubbard model

2019 ◽  
Vol 99 (4) ◽  
Author(s):  
Daniel González-Cuadra ◽  
Alexandre Dauphin ◽  
Przemysław R. Grzybowski ◽  
Paweł Wójcik ◽  
Maciej Lewenstein ◽  
...  
Keyword(s):  
Symmetry Breaking ◽  
Hubbard Model ◽  
Topological Insulators

SYMMETRY BREAKING AND ORDER PARAMETERS OF THE HUBBARD MODEL

1992 ◽  
Vol 06 (03) ◽  
pp. 151-159 ◽  
Author(s):  
ROBERTO LIVI ◽  
ARIANNA MONTORSI ◽  
MARIO RASETTI
Keyword(s):  
Symmetry Breaking ◽  
Hubbard Model ◽  
Order Parameter ◽  
Order Parameters ◽  
Global Symmetry ◽  
Linearization Technique ◽  
Disordered Phase ◽  
Complete Symmetry

The effects of different linearization procedures as breaking of the global symmetry of the Hubbard model recently discovered by Yang and Zhang are discussed, together with the ensuing order parameters. In particular it is pointed out how only the Fermi linearization technique allows us both to restore the complete symmetry in the disordered phase, and to describe an ordered phase characterized by an order parameter associated with the breaking of the superconductive symmetry.

scholarly journals CHIRAL SYMMETRY BREAKING AT NONZERO CHEMICAL POTENTIAL

2006 ◽  
Vol 21 (04) ◽  
pp. 859-864 ◽  
Author(s):  
J. C. Osborn ◽  
K. Splittorff ◽  
J. J. M. Verbaarschot
Keyword(s):  
Partition Function ◽  
Symmetry Breaking ◽  
Dirac Operator ◽  
Chiral Symmetry ◽  
Chemical Potential ◽  
Chiral Symmetry Breaking ◽  
Chiral Condensate ◽  
Zero Temperature ◽  
Dirac Spectrum

We consider chiral symmetry breaking at nonzero chemical potential and discuss the relation with the spectrum of the Dirac operator. We solve the so called Silver Blaze Problem that the chiral condensate at zero temperature does not depend on the chemical potential while this is not the case for the Dirac spectrum and the weight of the partition function.

Localization in the Hopping Disordered Bose Hubbard Model

1998 ◽  
Vol 12 (28) ◽  
pp. 1159-1166 ◽  
Author(s):  
K. Sheshadri
Keyword(s):  
Hubbard Model ◽  
Density Of States ◽  
Order Parameter ◽  
Singular Part ◽  
Low Energy ◽  
Strongly Correlated ◽  
Zero Temperature ◽  
Bose Glass ◽  
Dynamical Exponents ◽  
Approximation Calculation

The zero-temperature superfluid (SF)–Bose glass (BG) transition in the strongly correlated (U=∞) Bose Hubbard model in d dimensions driven by disorder in hopping is studied using a simple analytic technique. The transition is identified as the point at which the density of states for local rotations of phase of the superfluid order parameter is enhanced at the lowest energies. This identification leads to the values ν=2/d and z=d/2 for the correlation length and dynamical exponents, respectively, by an approximation calculation of the low-energy density of states for large d. At the transition, the singular part of the compressibility κ vanishes, so κ is finite.

EFFECTIVE POTENTIALS FOR ϕ4-THEORY IN 2+1 DIMENSIONS

1994 ◽  
Vol 09 (28) ◽  
pp. 2623-2635 ◽  
Author(s):  
R.A. OLSEN ◽  
F. RAVNDAL
Keyword(s):  
Transition Temperature ◽  
Symmetry Breaking ◽  
Effective Potential ◽  
Gaussian Approximation ◽  
Critical Value ◽  
Zero Temperature ◽  
Coupling Constant ◽  
Effective Potentials ◽  
Bare Coupling Constant ◽  
Symmetric Phase

Spontaneous symmetry breaking in ϕ4-theory in 2+1 dimensions is investigated using the Gaussian approximation. The theory stays in the symmetric phase at zero temperature as long as the bare coupling constant is below a critical value λc. When λ>λc the symmetric phase is again stable when the temperature is above a transition temperature T(λ). The obtained results are compared with the predictions of the standard one-loop effective potential.

Sign in / Sign up

Export Citation Format

Share Document