Effect of density of state on isotope effect exponent of two-band superconductors

Abstract

The exact formula of Tc's equation and the isotope effect exponent of two-band s-wave superconductors in weak-coupling limit are derived by considering the influence of two kinds of density of state : constant and van Hove singularity. The pairing interaction in each band consisted of 2 parts : the electron-phonon interaction and non-electron-phonon interaction are included in our model. We find that the interband interaction of electron-phonon show more effect on isotope exponent than the intraband interaction and the isotope effect exponent with constant density of state can fit to an experimental data,MgB2, and high-Tc superconductors, better than van Hove singularity density of state.

11 pages. accepted in Physica C

References in corpus (16)

• Beyond Eliashberg superconductivity in MgB2: anharmonicity, two-phonon scattering, and multiple gaps
• Boron Isotope Effect in Superconducting MgB${}_2$
• Electron-phonon interaction in the normal and superconducting states of MgB2
• Evidence for two superconducting energy gaps in MgB2 by point-contact spectroscopy
• Specific Heat of Mg ^{11}B_2
• Two Gap State Density in MgB${}_2$: A True Bulk Property or A Proximity Effect?
• Specific heat in the superconducting and normal state (2-300 K, 0-16 Teslas), and magnetic susceptibility of the 38-K superconductor MgB2: evidence for a multicomponent gap
• Phenomenological two-gap model for the specific heat of MgB_2
• The reduced total isotope effect and its implications on the nature of superconductivity in MgB2
• Evidence for Two Superconducting Gaps in $Mg{B}_2$
• Direct evidence for a multiple superconducting gap in MgB2 from high-resolution photoemission spectroscopy
• Strong Electron-Phonon Coupling in Superconducting MgB${}_2$: A Specific Heat Study
• Relation of Extended Van Hove Singularities to High-Temperature Superconductivity within Strong-Coupling Theory
• Unusual effects of anisotropy on the specific heat of ceramic and single crystal MgB2
• The Isotope Effect in d-Wave Superconductors
• Isotope effect in the presence of a pseudogap

Cited by in corpus (2)

• Effect of interband interactions of phonon and charge fluctuation on superconducting parameters of MgB2
• Investigate the effect of anisotropic order parameter on the specific heat of anisotropic two-band superconductors