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arXiv · 1408.0271

Nonmetallic Low-Temperature Normal State of K0.70Fe1.46Se1.85Te0.15

Kefeng Wang·Hyejin Ryu·Erik Kampert·M. Uhlarz·J. Warren·J. Wosnitza·C. Petrovic
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Abstract

The normal-state in-plane resistivity below the zero-field superconducting transition temperature $T_c$ and the upper critical field Hc2 were measured by suppressing superconductivity in pulsed magnetic fields for K0.70Fe1.46Se1.85Te0.15. The normal-state resistivity $\rho_{ab}$ is found to increase logarithmically with decrasing temperature as $\frac{T}{T_c}\rightarrow 0$. Similar to granular metals, our results suggest that a superconductor - insulator transition below zero-field T$_{c}$ may be induced in high magnetic fields. This is related to the intrinsic real-space phase-separated states common to all inhomogeneous superconductors.

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Kefeng Wang, Hyejin Ryu, Erik Kampert, M. Uhlarz, J. Warren, J. Wosnitza, C. Petrovic. 2014-08-01. Nonmetallic Low-Temperature Normal State of K0.70Fe1.46Se1.85Te0.15. https://doi.org/10.1103/physrevx.4.031018

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