arXiv subjects

C. Kumvongsa

Publications and source records attributed to C. Kumvongsa.

4 recordsLinked to original sources

arXiv2009

Investigate the effect of anisotropic order parameter on the specific heat of anisotropic two-band superconductors

The effect of anisotropic order parameter to specific heat of anisotropic two-band superconductors in BCS weak-coupling limit are investigated. An analytical specific heat jump and the numerical specific heat are shown by using anisotropic order parameters, and the electron-phonon interaction and non-electron-phonon interaction. The two model of anisotropic order parameters are used for numerical calculation that we find little effect to the numerical results . The specific heat jump of, and superconductors can fit well with the both of them. By comparing to experimental data overall range of temperature, the best fit is ,, and superconductors, respectively.

cond-mat.supr-con↗

arXiv2005

Hc2 of anisotropy two-band superconductors by Ginzburg-Landau approach

The purpose of this research is to study the upper critical field (Hc2) of two-band superconductors by two-band Ginzburg - Landau approach. The analytical formula of Hc2 included anisotropy of order parameter and anisotropy of effective-mass are found . The parameters of the upper critical field in ab-plane and c-axis can be found by fitting to the experimental data . Finally, we can find the ratio of upper critical field that temperature dependent in the range of experimental result .

cond-mat.supr-con↗

arXiv2005

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

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.

cond-mat.supr-con↗

arXiv2004

Influence of interband interaction on Isotope Effect Exponent of MgB2 Superconductors

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 interband interaction. The paring interaction in each band consisted of 2 parts : the electron-phonon interaction and non-phonon interaction are included in our model. The isotope effect exponent of MgB2 equal to 0.3 with Tc 40 K can be found in the weak coupling regime and interband interaction of electron-phonon interaction show more effect on isotope effect exponent than of non-phonon interaction.

cond-mat.supr-con↗