Impact of nematicity on the relationship between antiferromagnetic fluctuations and superconductivity in FeSe0.91S0.09 under pressure

K. Rana; L. Xiang; P. Wiecki; R. A. Ribeiro; G. G. Lesseux; A. E. Böhmer; S. L. Bud'ko; P. C. Canfield; Y. Furukawa

doi:10.1103/PhysRevB.101.180503

← Back to search

Impact of nematicity on the relationship between antiferromagnetic fluctuations and superconductivity in FeSe0.91S0.09 under pressure

K. Rana, L. Xiang, P. Wiecki, R. A. Ribeiro, G. G. Lesseux, A. E. Böhmer, S. L. Bud'ko, P. C. Canfield, Y. Furukawa

DOI 10.1103/PhysRevB.101.180503 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

The sulfur-substituted FeSe system, FeSe1−xSx, provides a versatile platform for studying the relationship among nematicity, antiferromagnetism, and superconductivity. Here, by nuclear magnetic resonance (NMR) and resistivity measurements up to 4.73 GPa on FeSe0.91S0.09, we established the pressure- (p-) temperature (T) phase diagram in which the nematic state is suppressed with pressure showing a nematic quantum phase transition (QPT) around p=0.5GPa, two superconductivity (SC) regions separated by the QPT appear, and antiferromagnetic (AFM) phase emerges above ∼3.3GPa. From the NMR results up to 2.1 GPa, AFM fluctuations are revealed to be characterized by the stripe-type wave vector which remains the same for the two SC regions. Furthermore, the electronic state is found to change in character from non-Fermi liquid to Fermi liquid around the nematic QPT and persists up to ∼2.1GPa. In addition, although the AFM fluctuations correlate with Tc in both SC states, demonstrating the importance of the AFM fluctuations for the appearance of SC in the system, we found that, when nematic order is absent, Tc is strongly correlated with the AFM fluctuations whereas Tc weakly depends on the AFM fluctuations when nematic order is present. Our findings on FeSe0.91S0.09 were shown to be applied to the whole FeSe1−xSx system and provide an insight into the relationship between AFM fluctuations and SC in Fe-based superconductors.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
FeSe0.91S0.09 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	8.5	Pressure unresolved	unknown
FeSe Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	8.5	Pressure unresolved	unknown
FeS Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	5	Pressure unresolved	unknown
FeSe0.91S0.09 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
FeSe0.91S0.09 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown