Electronic-structure calculation of the hole-carrier-density distribution in Bi[sub 2]Sr[sub 2]CuO[sub 6], Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8], and Bi[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 10] superconductors

Journal Article · Sun May 01 00:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.49.13154· OSTI ID:6716052

Gupta, R P ^[1]; Gupta, M ^[2]

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1. Section de Recherches de Metallurgie Physique, Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette Cedex (France)
2. Institut des Sciences des Materiaux, Universite de Paris-Sud, Batiment 415, 91405 Orsay (France)

Results of electronic structure calculations for the hole density in the two-dimensional CuO[sub 2] planes are presented in this paper for the three bismuth cuprate superconductors Bi[sub 2]Sr[sub 2]CuO[sub 6], Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8], and Bi[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 10]. The hole density in these compounds arises due to electron transfer from the CuO[sub 2] planes to the Bi-O layers. Our calculations show that Bi[sub 2]Sr[sub 2]CuO[sub 6] is so highly overdoped that it is really a metal and at the limit of superconductivity. Also Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8] has a hole density which is higher than is required for a maximum value of [ital T][sub [ital c]]. On the other hand, the hole density in the three-layer compound Bi[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 10] is nearly optimum, which indicates that apart from the number of layers, an optimum value of the hole density is important for maximizing [ital T][sub [ital c]]. The hole densities in the two types of CuO[sub 2] layers in this compound are nearly equal although the central layer has a slightly lower value. As the number of CuO[sub 2] planes increases in this family of superconductors the total amount of hole carrier density per chemical formula increases due to an enhanced electron transfer to the Bi-O layers. However, this increase is small so that the hole density per CuO[sub 2] drops rapidly as the number of CuO[sub 2] planes increases.

• OSTI ID: 6716052
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 49:18; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH OXIDES
CRYSTAL STRUCTURE
ELECTRONIC STRUCTURE
HOLES
CALCIUM OXIDES
CUPRATES
STRONTIUM OXIDES
CARRIER DENSITY
ELECTRON TRANSFER
TRANSITION TEMPERATURE
VALENCE
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
STRONTIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
360207* - Ceramics
Cermets
& Refractories- Superconducting Properties- (1992-)