The Origin of Condensation Energy Scaling of the Fe-based superconductors

Abstract

Motivated by the recent experiment of the non-BCS scaling relation of the condensation energy $\Delta CE$ vs. $T_c$ ($\Delta CE\sim T_c^{\beta },\beta \approx 3.5$) [PRB 89 140503 (2014)] for the Fe-based superconductors, we studied the CE and $T_c$ of the multiband BCS superconductors. We showed that the experimentally observed anomalous scaling relation $\Delta CE\sim T_c^{3.5}$ is well reproduced by the two-band BCS superconductor paired by a dominant interband interaction ($V_{inter}>V_{intra}$). Our result implies that this seemingly non-BCS-like scaling behavior, on the contrary to the common expectation, is in fact a strong experimental evidence that the pairing mechanism of the Fe-based superconductors is genuinely a BCS mechanism, meaning that "the Cooper pairs are formed by the itinerant carriers glued by a pairing interaction."

7 pages, 4 figures

References in corpus (8)

• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Superfluid density of the $\pm$s-wave state for the iron-based superconductors
• Fe-based superconductors: seven years later
• Possible pairing states of the Fe-based superconductors
• Interband superconductivity: contrasts between BCS and Eliashberg theory
• A doping dependent specific heat study of the superconducting gap in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Effect of annealing on the specific heat of Ba(Fe1-xCox)2As2
• Specific Heat Discontinuity DeltaC vs Tc in Annealed Ba(Fe1-xCox)2As2

Cited by in corpus (2)

• Superconducting Properties of the $s^{\pm }$-wave state: Fe-based superconductors
• Pairing Mechanism of the Heavily Electron Doped FeSe Systems: Dynamical Tuning of the Pairing Cutoff Energy