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arXiv · 2009.05339

Enhanced critical temperatures in the strongly overdoped iron-based superconductors AFe$_2$As$_2$ (A = K, Cs, Rb) observed by point contacts

Yu. G. Naidyuk·O. E. Kvitnitskaya·D. V. Efremov·S. -L. Drechsler
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Abstract

A remarkable several times increase (up to 10 K) of the superconducting critical temperature Tc has been observed in point contacts created on the base of single crystals AFe$_2$As$_2$ (A = K, Cs, Rb). Possible reasons for such a Tc increase in point contacts are briefly discussed on a qualitative level. Among them, it is most likely attributed to interfacial carrier doping and/or uniaxial non-homogeneous pressure arising when the contact is created.

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Yu. G. Naidyuk, O. E. Kvitnitskaya, D. V. Efremov, S. -L. Drechsler. 2020-09-11. Enhanced critical temperatures in the strongly overdoped iron-based superconductors AFe$_2$As$_2$ (A = K, Cs, Rb) observed by point contacts. https://doi.org/10.1063/10.0002149

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