Absence of an appreciable iron isotope effect on the transition temperature of the optimally doped SmFeAsO_{1-y} superconductor

Parasharam M. Shirage; Kiichi Miyazawa; Kunihiro Kihou; Hijiri Kito; Yoshiyuki Yoshida; Yasumoto Tanaka; Hiroshi Eisaki; Akira Iyo

doi:10.1103/physrevlett.105.037004

arXiv · 1007.2666

Absence of an appreciable iron isotope effect on the transition temperature of the optimally doped SmFeAsO_{1-y} superconductor

Parasharam M. Shirage·Kiichi Miyazawa·Kunihiro Kihou·Hijiri Kito·Yoshiyuki Yoshida·Yasumoto Tanaka·Hiroshi Eisaki·Akira Iyo

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Abstract

We report the iron (Fe) isotope effect on the transition temperature (Tc) in the oxygen-deficient SmFeAsO_{1-y}, a 50 K-class Fe-based superconductor. For the optimally-doped samples with Tc = 54 K, change of the Fe average atomic mass (MFe) causes a negligibly small shift in Tc, with the Fe isotope coefficient (alphaFe) as small as -0.024 \pm 0.015. This result contrasts with the finite, inverse isotope shift observed in optimally-doped (Ba,K)Fe2As2, indicating that the contribution of the electron-phonon interaction markedly differs between these two Fe-based high-Tc superconductors.

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Parasharam M. Shirage, Kiichi Miyazawa, Kunihiro Kihou, Hijiri Kito, Yoshiyuki Yoshida, Yasumoto Tanaka, Hiroshi Eisaki, Akira Iyo. 2010-07-15. Absence of an appreciable iron isotope effect on the transition temperature of the optimally doped SmFeAsO_{1-y} superconductor. https://doi.org/10.1103/physrevlett.105.037004

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