Metastable behavior of the superconducting phase in the BaBi sub 1 minus x Pb sub x O sub 3 system

Journal Article · Wed Jul 01 04:00:00 EDT 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.46.1144· OSTI ID:5002408

Marx, D T; Radaelli, P G; Jorgensen, J D; Hitterman, R L; Hinks, D G; Pei, S; Dabrowski, B ^[1]

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1. Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

The structural phases of the BaBi{sub 1{minus}{ital x}}Pb{sub {ital x}}O{sub 3} system have been studied using neutron powder diffraction. As lead is substituted on the bismuth site, the room-temperature structure is monoclinic for 0.00{le}{ital x}{le}0.20, orthorhombic for 0.25{le}{ital x}{le}0.65, diphasic (orthorhombic and tetragonal) for 0.70{le}{ital x}{le}0.80, and monoclinic for {ital x}=1.0. Superconductivity is observed for samples in the composition range 0.70{le}{ital x}{le}0.80. The superconducting phase is the tetragonal phase. {ital In} {ital situ} neutron-powder-diffraction measurements versus temperature show that it is not stable at temperatures below about 425 K. All superconducting samples consist of the metastable tetragonal phase and a semiconducting orthorhombic phase because the tetragonal-to-orthorhombic transition does not proceed to completion. Samples of Ba{sub 1{minus}{ital y}}K{sub {ital y}}Bi{sub 1{minus}{ital x}}Pb{sub {ital x}}O{sub 3} have {ital T}{sub {ital c}}'s that are inversely proportional to the total dopant concentration, {ital x}+{ital y}, in the composition region (0.5{le}{ital x}+{ital y}{le}0.9), where the material is metallic.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5002408
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 46:2; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360207 -- Ceramics
Cermets
& Refractories-- Superconducting Properties-- (1992-)
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
BISMUTH COMPOUNDS
BISMUTH OXIDES
CHALCOGENIDES
COHERENT SCATTERING
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ENERGY LEVELS
EXCITED STATES
LEAD COMPOUNDS
LEAD OXIDES
METASTABLE STATES
NEUTRON DIFFRACTION
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SCATTERING
SUPERCONDUCTIVITY