Superconductivity up to 90 K in a new family of the (Pb,Hg)Sr[sub 2](Ca,Y)Cu[sub 2]O[sub 7] system

Journal Article · Mon Mar 01 04:00:00 EST 1993 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1993.1101· OSTI ID:6351141

Hu, S F; Jefferson, D A ^[1]; Liu, R S ^[2]; Edwards, P P ^[3]

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1. Univ. of Cambridge (United Kingdom)
2. Univ. of Cambridge (United Kingdom) Industrial Technology Research Inst., Hsinchu (Taiwan, Province of China)
3. Univ. of Birmingham (United Kingdom)

A new family of superconductors were observed in the (Pb[sub 0.5]Hg[sub 0.5])Sr[sub 2](Ca[sub 1[minus]x]Y[sub x])Cu[sub 2]O[sub 7[minus][delta]] system for the composition range 0.5 [le] x [le] 0.2, with a maximum [Tc] of 90 K (at x = 0.3) as determined by electrical resistance and magnetization measurements. The authors have investigated the crystal structure across the entire composition range by X-ray diffraction, by which they identify the phase responsible for the superconductivity to be similar to that of (Pb,Cu)Sr[sub 2]CaCu[sub 2]O[sub 7] (the so-called Pb-based 1212 phase) with a space group of P4/mmm and lattice constants of a ranging from 3.8159(6) [Angstrom] for x = 0.5 to 3.8082(4) [Angstrom] for x = 0.2, and c ranging from 11.950(2) [Angstrom] for x = 0.5 to 12.022(2) [Angstrom] for x = 0.2. Moreover, the chemical composition of one sample in the series having nominal composition (Pb[sub 0.5]Hg[sub 0.5])Sr[sub 2](Ca[sub 0.5]Y[sub 0.5]) Cu[sub 2]O[sub 7[minus][delta]] (x = 0.5) was determined to be [Pb[sub 0.6]Hg[sub 0.2]Cu[sub 0.2]]Sr[sub 2.0][Ca[sub 0.42]Y[sub 0.51]Hg[sub 0.07]]Cu[sub 2]O[sub 7[minus][delta]] by energy-dispersive spectrometry. 23 refs., 5 figs.

• OSTI ID: 6351141
• Journal Information: Journal of Solid State Chemistry; (United States), Journal Name: Journal of Solid State Chemistry; (United States) Vol. 103:1; ISSN 0022-4596; ISSN JSSCBI
• 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
CHALCOGENIDES
CHEMICAL COMPOSITION
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
HIGH-TC SUPERCONDUCTORS
LATTICE PARAMETERS
LEAD COMPOUNDS
LEAD OXIDES
MAGNETIZATION
MERCURY COMPOUNDS
MERCURY OXIDES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
STOICHIOMETRY
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES