Soft-x-ray-absorption studies of Tl sub 2 Ba sub 2 Ca sub 2 Cu sub 3 O sub 10 minus. delta. high- T sub c superconductors

Journal Article · Fri May 01 00:00:00 EDT 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.45.10051· OSTI ID:7048176

Krol, A; Lin, C S; Soo, Y L; Ming, Z H; Kao, Y H ^[1]; Wang, J H; Qi, M ^[2]; Smith, G C ^[3]

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1. Department of Physics and New York State Institute on Superconductivity, State University of New York at Buffalo, Buffalo, New York 14260 (United States)
2. Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260 (United States)
3. Brookhaven National Laboratory, Upton, New York 11973 (United States)

X-ray absorption around the oxygen {ital K} and the Cu {ital L}{sub III} edge of Tl{sub 2}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10{minus}{delta}} high-{ital T}{sub {ital c}} superconductors with different oxygen content {delta}, was measured. Near the O 1{ital s} edge, three distinct pre-edge peaks with maxima at 528.3, 529.4, and 530.6 eV, respectively, are revealed. They are ascribed to core-level excitations of oxygen 1{ital s} electrons to empty states which have predominantly oxygen 2{ital p} character, located in CuO{sub 2}, BaO, and TlO planes, respectively. A strong dependence of {ital T}{sub {ital c}} on oxygen hole concentration at O(1) and O(1){prime} sites in the CuO{sub 2} layer is found. Near the Cu 2{ital p}{sub 3/2} edge, two main peaks are observed. The peak at 931.2 eV is ascribed to a 2{ital p}3{ital d}{sup 10} final state. This implies a predominately Cu{sup 2+} ground state which has mainly 3{ital d}{sup 9} character. The peak at 933 eV is ascribed to a 2{ital p}3{ital d}{sup 10}{ital L} final state. This peak shows an intensity increase with {ital T}{sub {ital c}}, i.e., with ligand hole concentration, and is believed to arise from a formally Cu{sup 3+} ground state which has mainly 3{ital d}{sup 9}{ital L} character. No evidence of a monovalent (Cu{sup 1+}) 3{ital d}{sup 10} ground state was found.

• DOE Contract Number: FG02-87ER45283; AC02-76CH00016
• OSTI ID: 7048176
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 45:17; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
ELECTRONIC STRUCTURE
CALCIUM OXIDES
COPPER OXIDES
THALLIUM OXIDES
ABSORPTION SPECTRA
GROUND STATES
HIGH-TC SUPERCONDUCTORS
LIGANDS
SOFT X RADIATION
TRANSITION TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
ELECTROMAGNETIC RADIATION
ENERGY LEVELS
IONIZING RADIATIONS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIATIONS
SPECTRA
SUPERCONDUCTORS
THALLIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
X RADIATION
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