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Phenomenological two-gap model for the specific heat of MgB_2

F. Bouquet·Y. Wang·R. A. Fisher·D. G. Hinks·J. D. Jorgensen·A. Junod·N. E. Phillips
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Abstract

We show that the specific heat of the superconductor MgB_2 (MgB2) in zero field, for which significant non-BCS features have been reported, can be fitted, essentially within experimental error, over the entire range of temperature to T_c by a phenomenological two-gap model. The resulting gap parameters agree with previous determinations from band-structure calculations, and from various spectroscopic experiments. The determination from specific heat, a bulk property, shows that the presence of two superconducting gaps in MgB_2 is a volume effect.

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F. Bouquet, Y. Wang, R. A. Fisher, D. G. Hinks, J. D. Jorgensen, A. Junod, N. E. Phillips. 2001-10-22. Phenomenological two-gap model for the specific heat of MgB_2. https://doi.org/10.1209/epl%2Fi2001-00598-7

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