Positron-annihilation studies on the Bi-Sr-Ca-Cu-O superconductor

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.13019· OSTI ID:5490724

Sundar, C S; Bharathi, A; Ching, W Y; Jean, Y C ^[1]; Hor, P H; Meng, R L; Huang, Z J; Chu, C W ^[2]

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1. University of Missouri, Kansas City, Missouri 64110 (USA)
2. Texas Center for Superconductivity, University of Houston, Houston, Texas 77024-5506 (USA)

The results of positron-lifetime measurements as a function of temperature, across {ital T}{sub {ital c}}, and as a function of heat treatment are presented. The lifetime in Bi-Sr-Ca-Cu-O does not show any variation with temperature in the range of 10 to 300 K, a result that is in contrast with other cuprate superconductors. The absence of lifetime variation across {ital T}{sub {ital c}} is understood in terms of the calculated positron-density distribution, which indicates that the maximum of the positron density is in the region between the Bi-O layers with no significant density in the superconducting CuO{sub 2} layers. Positron-lifetime measurements as a function of heat treatment indicate a decrease in lifetime as the annealing temperature is lowered from 800{degree}C to 100{degree}C. The decrease in lifetime, which is correlated with the increase in the weight of the sample, is explained in terms of the intercalation of the excess oxygen in the region between the Bi-O layers, which is the region probed by the positron.

• OSTI ID: 5490724
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:16; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
ANNEALING
ANNIHILATION
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
BASIC INTERACTIONS
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
FERMIONS
HEAT TREATMENTS
HIGH-TC SUPERCONDUCTORS
INTERACTIONS
LEPTONS
LIFETIME
MATTER
OXIDES
OXYGEN COMPOUNDS
PARTICLE INTERACTIONS
POSITRONS
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TRANSITION ELEMENT COMPOUNDS