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

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 $\frac{T}{T_c}\to 0$. 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.

6 pages, 4 figures

References in corpus (10)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Quantum Criticality in Heavy Fermion Metals
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Nearly Isotropic superconductivity in (Ba,K)Fe2As2
• Observation of Temperature-Induced Crossover to an Orbital-Selective Mott Phase in A${}_x$Fe${}_{2-y}$Se${}_2$ (A=K, Rb) Superconductors
• Orbital-selective Mott Phase in Multiorbital Models for Alkaline Iron Selenides K(1-x)Fe(2-y)Se2
• Phase relations in K_xFe_{2-y}Se_2 and the structure of superconducting K_xFe_2Se_2 via high-resolution synchrotron diffraction
• High-Field Pauli-Limiting Behavior and Strongly Enhanced Upper Critical Magnetic Fields near the Transition Temperature of an Arsenic-Deficient LaO_0.9F_0.1FeAs_(1-δ) Superconductor
• Overview on the physics and materials of the new superconductor KxFe2-ySe2
• Implication of the Mott-limit violation in high-Tc cuprates