Phenomenological two-gap model for the specific heat of MgB₂

2001/07/31 by F. Bouquet, Y. Wang, R. A. Fisher +4 · 1 citation
Physics and Astronomy · #cond-mat.supr-con

paper · pdf · doi:10.1209/epl/i2001-00598-7

published as Europhysics Letters 56, 856 (2001) · 7 pages, 4 figures Accepted for publication in Europhysics Letters Text is unchanged. Figure 1 was made clearer (labels). We tried to update cond-mat references from the bibliography which were published (before october 5th)

arxiv created 2001/10/22 · arxiv updated 2009/11/30

Abstract

We show that the specific heat of the superconductor MgB₂ (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 MgB₂ is a volume effect.

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