Abstract
We present results of Raman and infrared spectroscopic studies of the composite system of superconducting YBa2Cu3O7-δ and metallic BaPbO3, with the BaPbO3 fraction ranging from 5 to 30 in weight. The Raman spectra of the YBa2Cu3O7-δ grains in the composite system are typical of well-oxygenated YBa2Cu3O7-δ bulk single crystals, even up to the grain boundaries, independent of the BaPbO3 fraction. We have also performed infrared reflectivity measurements and have identified the major c-axis transverse-optical phonons of YBa2Cu3O7-δ, consistent with the single-crystal data, confirming that the constituent YBa2Cu3O7-δ crystallites are fully oxygenated. The absence of mode splitting suggests that the crystal symmetry of YBa2Cu3O7-δ grains remains the same as that of bulk single crystals. No phonons indicative of other YBa2Cu3O7- or BaPbO3-related impurity phases, such as YBa2Cu3O6, Y2BaCuO5, and Ba2PbO4, have been detected in our Raman and infrared spectra. All these optical features clearly indicate that YBa2Cu3O7-δ is well separated from BaPbO3 and that BaPbO3 is an excellent additive material for the synthesis of YBa2Cu3O7-δ bulk materials.
Original language | English |
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Pages (from-to) | 60-66 |
Number of pages | 7 |
Journal | Physica C: Superconductivity and its Applications |
Volume | 308 |
Issue number | 1-2 |
DOIs | |
State | Published - 1 Nov 1998 |
Keywords
- BaPbO
- Infrared spectroscopy
- Intergranular material
- Raman spectroscopy
- YBaCuO