Extreme anisotropy and anomalous transport properties of heavily electron doped Lix(NH3)yFe2Se2 single crystals

Abstract

The missing hole packets near the Brillouin zone center render unique electronic structures to the heavily electron doped FeSe-based superconductors with Tc above 40 K. It challenges the existing scenario accounting for the nature of superconductivity in the iron-based family. Yet, one hurdle that has to be overcome is the materials complexity in the rather limited number of compounds. Here we report the growth of heavily electron doped Li-NH3 intercalated FeSe single crystals that are free of such complexities and allow access to the intrinsic superconducting properties. Our results show extremely large electronic anisotropy in both normal and superconducting states. Moreover, the anomalous transport properties appear in normal state, which are believed related to the anisotropy of relaxation time and/or temperature dependent electron carrier concentration. In view of the great chemical flexibility of intercalants, our findings provide novel platform to understanding of superconductivity origin of FeSe-related superconductors.

8 pages, 5 figures

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Cited by in corpus (8)

• Resilient nodeless $d$-wave superconductivity in monolayer FeSe
• High-Tc superconductivity up to 55 K under high pressure in the heavily electron doped Lix(NH3)yFe2Se2 single crystal
• Protonation-induced discrete superconducting phases in bulk FeSe single crystals
• Enhanced anisotropic superconductivity in the topological nodal-line semimetal InxTaS2
• Significant enhancement of critical current density in H+-intercalated FeSe single crystal
• Probing the direct factor for superconductivity in FeSe-Based Superconductors by Raman Scattering
• Enhanced superconductivity and anisotropy of FeTe0.6Se0.4 single crystals with Li-NH3 intercalation
• A disorder-sensitive emergent vortex phase identified in high-Tc superconductor (Li,Fe)OHFeSe