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Influence of interband interaction on Isotope Effect Exponent of MgB2 Superconductors

P. Udomsamuthirun·C. Kumvongsa·A. Burakorn·P. Changkanarth
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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 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.

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P. Udomsamuthirun, C. Kumvongsa, A. Burakorn, P. Changkanarth. 2004-06-22. Influence of interband interaction on Isotope Effect Exponent of MgB2 Superconductors. https://arxiv.org/abs/cond-mat/0406496

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