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Superconducting Properties of BaBi$_{3}$

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 نشر من قبل Neel Haldolaarachchige
 تاريخ النشر 2014
  مجال البحث فيزياء
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We report the superconducting properties of single crystals of the intermetallic perovskite-related compound BaBi$_{3}$. The superconducting transition temperature ($T_{c}=5.82$~K) was obtained from heat capacity measurements. Using the measured values for the critical fields $H_{c1}, H_{c2}$, and the specific heat $C$, we estimate the thermodynamic critical field $H_{c}$(0), coherence length $xi$(0), Debye temperature $Theta _{D}$ and coupling constant $lambda _{ep}$. $Delta C/gamma T_{c}$ and $lambda _{ep}$ suggest that BaBi$_{3}$ is a moderately coupled superconductor and $gamma $ suggests an enhanced density of states at the Fermi level. Electronic band structure calculations show a complex Fermi surface and a moderately high DOS at the Fermi level. Further analysis of the electronic specific heat shows that the superconducting properties are dominated by s-wave gap.



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