Superconducting gap anisotropy and phonon anomalies in single crystal NdBa{sub 2}Cu{sub 3}O{sub 7{minus}x}

Journal Article · Wed Oct 01 04:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.9116· OSTI ID:632648

Misochko, O V ^[1]; Kuroda, K; Koshizuka, N ^[2]

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1. Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka, Moscow region (Russia)
2. Superconductivity Research Laboratory, International Superconductivity Technology Center, Tokyo 135 (Japan)

The temperature dependence of the low-frequency part of electronic Raman scattering was investigated in single crystal NdBa{sub 2}Cu{sub 3}O{sub 7{minus}x} with light polarized within the CuO{sub 2} planes and along the c axis. From the electronic continuum redistribution below T{sub c}, the pair-breaking energy is derived and is shown to depend on polarization. The in-plane pair-breaking 2{Delta} peaks are located at 330 cm{sup {minus}1} for the A{sub 1g} symmetry and around 580 cm{sup {minus}1} for B{sub 1g}. If we assume that the pair-breaking peak position is a measure of the superconducting gap, these values are almost the same, as in YBa{sub 2}Cu{sub 3}O{sub 7{minus}x}, 2{Delta}/T{sub c} ratios being roughly 5.2 and 8.5. For the c-axis response we detect the pair-breaking peak between 400 and 500 cm{sup {minus}1} and there is also a small decrease in the intensity at frequencies below 200 cm{sup {minus}1}. We also discuss some phonon anomalies probably caused by the substitution of Ba{sup 2+} by Nd{sup 3+}. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 632648
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 14 Vol. 56; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANISOTROPY
BARIUM OXIDES
COPPER OXIDES
ENERGY GAP
HIGH-TC SUPERCONDUCTORS
NEODYMIUM OXIDES
PHONONS
POLARIZATION
RAMAN SPECTRA
YTTRIUM OXIDES