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arXiv · 1907.01015

Bulk superconductivity and role of fluctuations in the iron-based superconductor FeSe at high pressures

Elena Gati·Anna E. Böhmer·Sergey L. Bud'ko·Paul C. Canfield
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Abstract

The iron-based superconductor FeSe offers a unique possibility to study the interplay of superconductivity with purely nematic as well magnetic-nematic order by pressure (p) tuning. By measuring specific heat under p up to 2.36GPa, we study the multiple phases in FeSe using a thermodynamic probe. We conclude that superconductivity is bulk across the entire p range and competes with magnetism. Our analysis suggests that superconducting and magnetic fluctuations exist over a wide temperature range above the respective bulk transition temperatures, whenever magnetism is present. These observations highlight similarities between FeSe and underdoped cuprate superconductors where fluctuations play a crucial role.

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Elena Gati, Anna E. Böhmer, Sergey L. Bud'ko, Paul C. Canfield. 2019-07-01. Bulk superconductivity and role of fluctuations in the iron-based superconductor FeSe at high pressures. https://doi.org/10.1103/physrevlett.123.167002

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