Intrinsic and structural isotope effects in Fe-based superconductors

Abstract

The currently available results of the isotope effect on the superconducting transition temperature T_c in Fe-based high-temperature superconductors (HTS) are highly controversial. The values of the Fe isotope effect (Fe-IE) exponent α_Fe for various families of Fe-based HTS were found to be as well positive, as negative, or even be exceedingly larger than the BCS value α_BCS=0.5. Here we demonstrate that the Fe isotope substitution causes small structural modifications which, in turn, affect T_c. Upon correcting the isotope effect exponent for these structural effects, an almost unique value of α~0.35-0.4 is observed for at least three different families of Fe-based HTS.

4 pages, 2 figures

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Cited by in corpus (8)

• Superconductivity in Iron Compounds
• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• Multi-Band Superconductivity and the Steep Band -- Flat Band Scenario
• High temperature superconductivity in sulfur hydride under ultrahigh pressure: A complex superconducting phase beyond conventional BCS
• Influence of multiorbitals and anisotropic Coulomb interactions on isotope effect coefficient in doped Fe-based superconductors
• Isotope effect on the transition temperature $T_c$ in Fe-based superconductors: the current status
• Lattice expansion from isotope substitution in the Iron based superconductors
• Unconventional superconductivity mediated solely by isotropic electron-phonon interaction