Optical phonons in YBa sub 2 Cu sub 4 O sub 8 and Y sub 2 Ba sub 4 Cu sub 7 O sub 15 minus. delta

Journal Article · Fri Jun 01 00:00:00 EDT 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.11058· OSTI ID:6815595

Heyen, E T; Liu, R; Thomsen, C; Kremer, R; Cardona, M ^[1]; Karpinski, J; Kaldis, E; Rusiecki, S ^[2]

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1. Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-7000 Stuttgart 80, Federal Republic of Germany (DE)
2. Laboratorium fuer Festkoerperphysik, Eidgenoessische Technische Hochschule, 8093 Zuerich, (Switzerland)

We present Raman spectra of high-temperature superconducting single crystals of YBa{sub 2}Cu{sub 4}O{sub 8} and Y{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15{minus}{delta}}, differing from the well-known YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} by having double CuO chains. By performing polarization-dependent measurements, we were able to identify the symmetry of the observed phonons. In both materials, we detected four out of six Raman-allowed modes of the double Cu(1)-O(1) chains and assign the peaks to Cu(1) {ital A}{sub {ital g}} (250 cm{sup {minus}1}), O(1) {ital A}{sub {ital g}} (605 cm{sup {minus}1}), Cu(1) {ital B}{sub 3{ital g}} (314 cm{sup {minus}1}), and O(1) {ital B}{sub 2{ital g}} (228 cm{sup {minus}1}) in addition to the 5 {ital A}{sub {ital g}} phonons (in YBa{sub 2}Cu{sub 4}O{sub 8} near 104, 153, 341, 438, and 500 cm{sup {minus}1}), which are also present in the well-known YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}. Contrary to previous reports of Raman scattering on double-CuO{sub 2}-plane superconductors, {ital B}{sub 2{ital g}} and {ital B}{sub 3{ital g}} phonons can unambiguously be observed.

• OSTI ID: 6815595
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 41:16; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
PHONONS
RAMAN SPECTRA
COPPER OXIDES
YTTRIUM OXIDES
ASYMMETRY
MONOCRYSTALS
POLARIZATION
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
CRYSTALS
OXIDES
OXYGEN COMPOUNDS
QUASI PARTICLES
SPECTRA
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties