Annealing and structure studies on Tl-2223 and Tl-1223 crystals
Single crystals with nominal stoichiometry Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} (Tl-2223) and TlCa{sub 2}Ba{sub 2}Cu{sub 3}O{sub 9} (Tl-1223) have been annealed in flowing oxygen or nitrogen and the complete crystal structure determined by least-squares refinement of Mo K{alpha} x-ray diffraction data. Small atomic displacements are found after the anneals that are consistent with a model in which small amounts of Tl{sup 1+} present in the Tl-O layer are subsequently reversibly oxidized/reduced during mild oxygen/nitrogen anneals to Tl{sup 3+}. Despite substantial changes in oxygen content in the Tl-O layers with annealing, Meissner data show very modest shifts in the superconducting transition temperature, suggesting little change in the carrier concentration in the Cu-O{sub 2} planes. 2 refs.
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 5712667
- Report Number(s):
- SAND-91-0771C; CONF-910736-4; ON: DE91014903
- Resource Relation:
- Conference: International conference on materials and mechanisms of superconductivity, Kanazawa (Japan), 22-26 Jul 1991
- Country of Publication:
- United States
- Language:
- English
Growth of crystals and effects of oxygen annealing in the Bi-Ca-Sr-Cu-O and Tl-Ca-Ba-Cu-O superconductor system
|
journal | August 1988 |
Stoichiometry and irradiation effects in melt grown Tl-Ca-Ba-Cu-O single crystals
|
journal | February 1991 |
Structure studies on Tl-2122 and Tl-2223 superconductors
|
journal | January 1991 |
Annealing study on single crystal Tl-2223 superconductors
|
journal | April 1991 |
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Related Subjects
BARIUM OXIDES
ANNEALING
CALCIUM OXIDES
COPPER OXIDES
THALLIUM OXIDES
CRYSTAL STRUCTURE
HIGH-TC SUPERCONDUCTORS
STOICHIOMETRY
X-RAY DIFFRACTION
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
HEAT TREATMENTS
OXIDES
OXYGEN COMPOUNDS
SCATTERING
SUPERCONDUCTORS
THALLIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360201* - Ceramics
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360202 - Ceramics
Cermets
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