Superconductivity of Bi-III phase of elemental bismuth: Insights from muon-spin rotation and density functional theory

Rustem Khasanov; Hubertus Luetkens; Elvezio Morenzoni; Gediminas Simutis; Stephan Schönecker; Andreas Östlin; Liviu Chioncel; Alex Amato

doi:10.1103/PhysRevB.98.140504

Superconductivity of Bi-III phase of elemental bismuth: Insights from muon-spin rotation and density functional theory

Rustem Khasanov, Hubertus Luetkens, Elvezio Morenzoni, Gediminas Simutis, Stephan Schönecker, Andreas Östlin, Liviu Chioncel, Alex Amato

DOI 10.1103/PhysRevB.98.140504 · 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

Using muon-spin rotation the pressure-induced superconductivity in the Bi-III phase of elemental bismuth (transition temperature Tc≃7.05 K) was investigated. A Ginzburg-Landau parameter κ=λ/ξ=30(6) (λ is the magnetic penetration depth, ξ is the coherence length) was estimated, which turns out to be the highest among known single element superconductors. The temperature dependence of the superconducting energy gap [Δ(T)] reconstructed from λ−2(T) deviates from the weakly coupled BCS prediction. The coupling strength 2Δ/kBTc≃4.34 was estimated, thus implying that Bi-III stays within the strong-coupling regime. The density functional theory calculations suggest that superconductivity in Bi-III could be described within the Eliashberg approach with a characteristic phonon frequency ωln≃5.5 meV. An alternative pairing mechanism to the electron-phonon coupling involves the possibility of Cooper pairing induced by Fermi-surface nesting.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Bi Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	7.05	2.72 GPa	onset
Bi Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	7.05	2.72 GPa	onset
Bi Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	7	2.7 GPa	unknown
MgB2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	40	Pressure not reported	unknown
H3S Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	200	200 GPa	unknown
Li Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	17.5	30 GPa	unknown
Ca Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	25	220 GPa	unknown
Sc Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	20	100 GPa	unknown