I. Tifrea

Critical temperature of a van Hove superconductor with spin–charge separation

Abstract We studied a spin–charge separation superconductor with a van Hove density of states. The critical temperature and the influence of the Coulomb interaction have been calculated in the mean field model. We also calculated the Ginzburg–Landau coefficients as a function of temperature.

Superconductivity and critical coupling in non-Fermi liquids

The critical temperature of a superconductor with a non-Fermi liquid ground state has been calculated. The density of states has two different forms and is energy dependent. The critical values of the coupling factor λ were calculated. The constant density of states results are obtained as particular cases. These results are an extension of the work done by Grosu et al. [Phys. Rev. B56, 8298 (1997)].

Field-induced Bose-Einstein condensation of interacting dilute magnons in three-dimensional spin systems : A renormalization-group study

We use the renormalization-group method to study the magnetic field influence on the Bose-Einstein condensation of interacting dilute magnons in three-dimensional spin systems. We first considered a model with

Flow-equation method for a superconductor with magnetic correlations

SU(2)

Impurity states in van Hove superconductors

symmetry (universality class

The flow-equation method for the single impurity in a 2D superconductor

z=1

Fluctuation conductivity in layered d-wave superconductors near critical disorder

) and we obtain for the critical magnetic field a power law dependence on the critical temperature,

2Δ(0)/Tc ratio in d-wave superconductors

[{H}_{c}(T)\ensuremath{-}{H}_{c}(0)]\ensuremath{\sim}{T}^{2}

Virtual bound states in d-wave van Hove superconductors

. In the case of

Flow-equations for the model of hybridized bosons and fermions

U(1)