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

P. Udomsamuthirun·C. Kumvongsa·A. Burakorn·P. Changkanart·S. Yoksan
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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.

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P. Udomsamuthirun, C. Kumvongsa, A. Burakorn, P. Changkanart, S. Yoksan. 2005-07-04. Effect of density of state on isotope effect exponent of two-band superconductors. https://doi.org/10.1016/j.physc.2005.07.001

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