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