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arXiv · 1008.4540

Intrinsic and structural isotope effects in Fe-based superconductors

R. Khasanov·M. Bendele·A. Bussmann-Holder·H. Keller
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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.

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R. Khasanov, M. Bendele, A. Bussmann-Holder, H. Keller. 2010-08-26. Intrinsic and structural isotope effects in Fe-based superconductors. https://doi.org/10.1103/physrevb.82.212505

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