Superconducting Gap Anisotropy vs Doping Level in High-{ital T{sub c}} Cuprates

Journal Article · Mon Jul 01 04:00:00 EDT 1996 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.77.727· OSTI ID:286758

Kendziora, C ^[1]; Kelley, R J; Onellion, M ^[2]

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1. Code 6650, Naval Research Laboratory, Washington, D.C. 20375 (United States)
2. Physics Department, University of Wisconsin, Madison, Wisconsin 53706 (United States)

We report the results of electronic Raman scattering in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi2212) and Tl{sub 2}Ba{sub 2}CuO{sub 6+{delta}} (Tl2201) high-{ital T}{sub {ital c}} superconductors with variations in the oxygen content. Near optimal doping, both materials show gap anisotropy, with 2{Delta}/{ital k}{sub {ital BT}}{sub {ital c}} values of 7.2 ({ital B}{sub 1{ital g}}) vs 5.8 ({ital A}{sub 1{ital g}}) in Tl2201 and 8.5 ({ital B}{sub 1{ital g}}) vs 6.2 ({ital A}{sub 1{ital g}}) in Bi2212. However, overdoped samples exhibit a symmetry independent gap with 2{Delta}/{ital k}{sub {ital BT}}{sub {ital c}} ranging from 5.2 for Bi2212 ({ital T}{sub {ital c}}=57 K) to 3.9 in Tl2201 ({ital T}{sub {ital c}}=37 K). We compare the data with calculations using both isotropic {ital s}-wave and {ital d}-wave order parameters. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 286758
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 4 Vol. 77; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANISOTROPY
BARIUM OXIDES
BISMUTH OXIDES
CALCIUM OXIDES
CRYSTAL DOPING
CUPRATES
D WAVES
DOPED MATERIALS
ELECTRONIC STRUCTURE
ENERGY GAP
HIGH-TC SUPERCONDUCTORS
ORDER PARAMETERS
RAMAN SPECTRA
S WAVES
STRONTIUM OXIDES
TITANIUM OXIDES