Normal state above the upper critical field in Fe1+yTe1-x(Se,S)x

Wang, Aifeng; Kampert, Erik; Saadaoui, H.; Luetkens, H.; Hu, Rongwei; Morenzoni, E.; Wosnitza, J.; Petrovic, C.

doi:10.1103/PhysRevB.95.184504

Title: Normal state above the upper critical field in ${Fe}_{1 + y} {Te}_{1 - x} {(Se, S)}_{x}$

Journal Article · Wed May 03 04:00:00 UTC 2017 · Physical Review. B

DOI: https://doi.org/10.1103/PhysRevB.95.184504 · OSTI ID:1372446

Wang, Aifeng ^[1]; Kampert, Erik ^[2]; Saadaoui, H. ^[3]; Luetkens, H. ^[3]; Hu, Rongwei ^[1]; Morenzoni, E. ^[3]; Wosnitza, J. ^[4]; Petrovic, C. ^[1]

Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
Helmholtz-Zentrum Berlin (HZB), (Germany). Hochfeld Magnetlabor Dresden (HLD-EMFL)
Paul Scherrer Inst. (PSI), Villigen (Switzerland). Lab. for Muon Spin Spectroscopy
Helmholtz-Zentrum Berlin (HZB), (Germany). Hochfeld Magnetlabor Dresden (HLD-EMFL); Technical Univ. Dresden (Germany). Inst. for Solid State Physics

Here, we have investigated the magnetotransport above the upper critical field ( H _{c 2}) in Fe _1.14 Te _0.7 Se _0.3 , Fe _1.02 Te _0.61 Se _0.39 , Fe _1.05 Te _0.89 Se _0.11 , and Fe _1.06 Te _0.86 S _0.14 . The μ SR measurements confirm electronic phase separation in Fe _1.06 Te _0.86 S _0.14 , similar to Fe _{1 + y} Te _{1 - x} Se _x . We found that superconductivity is suppressed in high magnetic fields above 60 T, allowing us to gain insight into the normal-state properties below the zero-field superconducting transition temperature ( T _c ). We also show that the resistivity of Fe _1.14 Te _0.7 Se _0.3 and Fe _1.02 Te _0.61 Se _0.39 above H _{c 2} is metallic as T → 0 , just like the normal-state resistivity above T _c . On the other hand, the normal-state resistivity in Fe _1.05 Te _0.89 Se _0.11 and Fe _1.06 Te _0.86 S _0.14 is nonmetallic down to lowest temperatures, reflecting the superconductor-insulator transition due to electronic phase separation.

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Research Organization:: Brookhaven National Laboratory (BNL), Upton, NY (United States); Energy Frontier Research Centers (EFRC) (United States). Center for Emergent Superconductivity (CES)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

Grant/Contract Number:: SC0012704

OSTI ID:: 1372446

Report Number(s):: BNL--114042-2017-JA; KC0201050

Journal Information:: Physical Review. B, Journal Name: Physical Review. B Journal Issue: 18 Vol. 95; ISSN 2469-9950; ISSN PRBMDO

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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