Oxygen and rare-earth doping of the 90-K superconducting perovskite YBa/sub 2/Cu/sub 3/O/sub 7-//sub x/

Journal Article · Wed Jul 01 00:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.226· OSTI ID:6093743

Tarascon, J M; McKinnon, W R; Greene, L H; Hull, G W; Vogel, a E.M.

Structural, magnetic and electronic properties of compounds in the series RBa/sub 2/Cu/sub 3/O/sub 7-//sub x/ (R = Nd,Sm,..., and Lu) were studied. Resistivity, Meissner-effect, and shielding measurements have revealed superconductivity among all the rare-earth compounds, except La, Pr, and Tb, with critical temperatures T/sub c/ measured at the midpoint of the resistive transition ranging from 87 to 95 K. No depression of T/sub c/ was observed upon introduction of most of the rare-earth magnetic ions. Susceptibility measurements down to 1.6 K have shown that an antiferromagnetic ordering (most likely due to dipole-dipole interactions) occurs only for the Gd compound. Changes in oxygen content in these materials drastically affect their physical properties. The importance of the cooling rate during the synthesis of the sample has been correlated to oxygen content. T/sub c/'s are optimized by slow cooling. Annealing at 700/sup 0/C in oxygen pressure of 40 atmospheres slightly increase T/sub c/, while annealing under vacuum at 420/sup 0/C destroys T/sub c/ and induces a semiconducting behavior. These changes in oxygen content and T/sub c/ are perfectly reversible.

• Research Organization: Bell Communications Research, 331 Newman Springs Road, Red Bank, New Jersey 07701-7020
• OSTI ID: 6093743
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 36:1; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
ANNEALING
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
HEAT TREATMENTS
MAGNETIC PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PEROVSKITES
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SCATTERING
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES