High-pressure study of the Raman modes in YBa{sub 2}(Cu{sub 0.96}Ni{sub 0.04}){sub 4}O{sub 8}

Journal Article · Sun Aug 01 04:00:00 EDT 1999 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.60.4363· OSTI ID:357311

Payne, D J; Guha, S; Cai, Q; Chandrasekhar, M; Chandrasekhar, H R ^[1]; Venkateswaran, U D ^[2]; Jayaram, B; Ulanday, J ^[3]

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1. Department of Physics, University of Missouri, Columbia, Missouri 65211 (United States)
2. Department of Physics, Oakland University, Rochester, Michigan 48309 (United States)
3. Materials Science Program, Department of Physics, University of Nebraska--Omaha, Omaha, Nebraska 68182 (United States)

We present a study of the Raman phonons in YBa{sub 2}(Cu{sub 0.96}Ni{sub 0.04}){sub 4}O{sub 8} under hydrostatic pressure in the superconducting phase. A comparison with our earlier work on the undoped YBa{sub 2}Cu{sub 4}O{sub 8} shows that the pressure coefficients of two vibrational modes involving oxygen atoms differ significantly from those of the corresponding modes in the undoped material. These are the O(1) chain mode which shifts 33{percent} faster and the O(2)-O(3) in-phase mode which shifts 23{percent} slower than the undoped counterparts. The other Raman modes in the Ni-doped sample shift in a manner similar to the undoped material. The observed behavior of the O(1) chain and O(2)-O(3) in-phase modes in YBa{sub 2}(Cu{sub 0.96}Ni{sub 0.04}){sub 4}O{sub 8} under pressure and the softening of the Cu(1) A{sub g} mode frequency with increasing Ni doping suggest that the Ni atoms substitute for the Cu atoms in the chain, which in turn decreases the compressibility in the vicinity of the Cu(Ni) chain atom. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 357311
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 6 Vol. 60; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM COMPOUNDS
BARIUM OXIDES
CHAINS
COMPRESSIBILITY
COPPER OXIDES
CRYSTAL DOPING
HIGH-TC SUPERCONDUCTORS
NICKEL OXIDES
PHONONS
PRESSURE DEPENDENCE
RAMAN SPECTRA
YTTRIUM COMPOUNDS
YTTRIUM OXIDES