Superconductivity above 77 K in the R-Tl-Sr-Ca-Cu-O system (R represents rare earths)

Z. Z. Sheng; L. Sheng; X. Fei; A. M. Hermann

doi:10.1103/PhysRevB.39.2918

← Back to search

Superconductivity above 77 K in the R-Tl-Sr-Ca-Cu-O system (R represents rare earths)

Z. Z. Sheng, L. Sheng, X. Fei, A. M. Hermann

DOI 10.1103/PhysRevB.39.2918 · 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

Superconductivity at 80-90 K has been resistively and magnetically observed in the R-Tl-Sr-Ca-Cu-O systems (R represents the rare earths including Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu and excepting Ce) in which five metal elements all are required for the superconductivity. In particular, the Pr-Tl-Sr-Ca-Cu-O system and Tb-Tl-Sr-Ca-Cu-O system are the first superconducting systems above 77 K in which Pr or Tb are required for the superconductivity. We believe that even higher critical temperatures may be achieved by optimizing the starting composition and preparation conditions, and/or by further elemental substitutions.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Tl0.5Pb0.5Sr2CaCu2O7 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	85	Pressure not reported	unknown
Tl0.5Pb0.5Sr2Ca2Cu3O9 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	120	Pressure not reported	unknown