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arXiv · 1812.00443

Fast recovery of the pristine magnetic and structural phases in superconducting LaFeAsO$_{0.89}$F$_{0.11}$ by Mn/Fe substitution

S. Sanna·P. Carretta·M. Moroni·G. Prando·P. Bonfà·G. Allodi·R. De Renzi·A. Martinelli
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Abstract

We report on an experimental study of the effect of Mn impurities in the optimally doped LaFeAsO$_{0.89}$F$_{0.11}$ compound. The results show that a very tiny amount of Mn, of the order of 0.1\%, is enough to destroy superconductivity and to recover at low temperatures both the magnetic ground state and the orthorhombic structure of the pristine LaFeAsO parent compound. The results are discussed within a model where electron correlations enhance the Ruderman-Kittel-Kasuya-Yosida interaction among impurities.

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S. Sanna, P. Carretta, M. Moroni, G. Prando, P. Bonfà, G. Allodi, R. De Renzi, A. Martinelli. 2018-12-02. Fast recovery of the pristine magnetic and structural phases in superconducting LaFeAsO$_{0.89}$F$_{0.11}$ by Mn/Fe substitution. https://doi.org/10.1088/1361-648x%2Fab0234

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