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arXiv · 1212.1034

Hydrostatic and uniaxial pressure dependence of superconducting transition temperature of KFe2As2 single crystals

Sergey L. Bud'ko·Yong Liu·Thomas A. Lograsso·Paul C. Canfield
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Abstract

We present heat capacity, c-axis thermal expansion and pressure dependent, low field, temperature dependent magnetization for pressures up to ~ 12 kbar, data for KFe2As2 single crystals. Tc decreases under pressure with dTc/dP ~ -0.10 K/kbar. The inferred uniaxial, c-axis, pressure derivative is positive, dTc/dpc ~ 0.11 K/kbar. The data are analyzed in comparison with those for overdoped Fe-based superconductors. Arguments are presented that superconductivity in KFe2As2 may be different from the other overdoped, Fe-based materials in the 122 family.

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Sergey L. Bud'ko, Yong Liu, Thomas A. Lograsso, Paul C. Canfield. 2012-12-26. Hydrostatic and uniaxial pressure dependence of superconducting transition temperature of KFe2As2 single crystals. https://doi.org/10.1103/physrevb.86.224514

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