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Constraints from $T_c$ and the isotope effect for MgB$_2$

A. Knigavko·F. Marsiglio
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Abstract

With the constraint that $T_c = 39$ K, as observed for MgB$_2$, we use the Eliashberg equations to compute possible allowed values of the isotope coefficient, $β$. We find that while the observed value $β= 0.32$ can be obtained in principle, it is difficult to reconcile a recently calculated spectral function with such a low observed value.

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A. Knigavko, F. Marsiglio. 2001-05-26. Constraints from $T_c$ and the isotope effect for MgB$_2$. https://doi.org/10.1103/physrevb.64.172513

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