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NIST High Temp. Superconducting Materials (HTS) Database:

NIST Standard Reference Database 62

Last Update to Data Content: 1996

DOI: https://doi.org/10.18434/T4KP8J

Bibliographic Information

Title: Superconducting Transition Temperature Enhancement in YBa2Cu3O7 by Chemical Substitution and the Implications Thereof for the Upper Critical Magnetic Field
Author(s): J.J. Neumeier
Publication: Applied Physics Letters Volume: 61 Issue: 15 Year: 1992 Page(s): 1852-1854
Editor(s): Not Available
Publisher: American Institute of Physics
Language: English
Notes: Not Available
Keywords: Material Specification, Crystallography, Critical Temperature, Resistivity (normal state)

Materials and Properties

Y:123; [Y-Ba(La)-Cu-O]
Material Specification for Y:123; [Y-Ba(La)-Cu-O] Process: Solid State Reaction
Notes: "Specimens... were prepared by reacting well-mixed stoichiometric mixtures of high purity (99.98% or better) Y2O3, BaCO3, La2O3, and CuO in air at 925 °C for 24 h in ZrO crucibles. Subsequently, the specimens were reground in an agate mortar for 6 min followed by reaction at 925 °C for 24 h. This last step was repeated three times with 24 h reaction intervals and two times with 48 and 72 h reaction intervals at 930 °C before the specimens were finally reground and pressed into pellets. The pellets were placed in an oxygen stream and reacted for 48 h at 935 °C, cooled over 9 h to 430 °C, held there for 14 h, and finally cooled over 7 h to 30 °C."
Formula: YBa2-xLaxCu3Oy
Informal Name: Y:123
Chemical Family: Y-Ba(La)-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:

Crystallography for Y:123; [Y-Ba(La)-Cu-O]
Crystal System: Orthorhombic
Formula Units per Cell:
Space Group: Pmmm
Cell Parameters
x of Lax (formula units) y of Oy (formula units) Temp K a Å b Å c Å
0.00 6.957 296 3.8174 3.8855 11.676
0.01 6.954 296 3.8168 3.8850 11.670
0.02 6.964 296 3.8162 3.8863 11.671
0.03 6.971 296 3.8161 3.8859 11.673
0.04 6.966 296 3.8164 3.8863 11.667
0.05 6.981 296 3.8159 3.8858 11.671
0.06 6.957 296 3.8157 3.8867 11.666
0.08 6.947 296 3.8163 3.8876 11.664
0.10 6.937 296 3.8152 3.8867 11.663
0.11 6.949 296 3.8151 3.8871 11.660
0.12 6.971 296 3.8149 3.8866 11.661
0.14 6.974 296 3.8151 3.8866 11.658
Measurement Method: X-ray diffraction
"Lattice parameters were calculated from 31 x-ray diffraction peaks which were indexed to the Pmmm orthorhombic crystal structure." No additional measurement details were noted.

Cautions: Evaluated Data
Digitized data were obtained from Figure 2 of the paper.
Critical Temperature for Y:123; [Y-Ba(La)-Cu-O]
x of Lax (formula units) y of Oy (formula units) ΔTc (K) Critical Temperature (K)
0.00 6.957 2.0 91.3
0.01 6.954 1.4 92.0
0.02 6.964 1.2 92.6
0.03 6.971 1.0 93.2
0.04 6.966 1.0 93.7
0.05 6.981 1.0 93.8
0.06 6.957 1.0 94.0
0.08 6.947 1.5 94.0
0.10 6.937 2.4 93.6
0.11 6.949 2.1 93.6
0.12 6.971 2.4 93.3
0.14 6.974 3.4 92.0
Measurement Method: Four-probe method
"Electrical resistivity was measured with a standard four-contact dc technique whereby reversal of the current direction cancels out thermoelectric voltages. Typical current densities for this measurement were 300 mA/cm2. Temperature was measured to an absolute accuracy of ±0.05 K with a calibrated Pt thermometer which was thermally anchored next to the specimen on the Cu sample holder. Absolute values of the electrical resistivities were determined by geometric measurements of the specimens with an experimental uncertainty of ±10%."

Cautions: Evaluated Data
Digitized data were obtained from Figure 3 of the paper.
Resistivity (normal state) for Y:123; [Y-Ba(La)-Cu-O]
x of Lax (formula units) y of Oy (formula units) Temperature (K) Resistivity (normal state) (mΩ·cm)
0 6.957 90.2 0.00
0 6.957 90.9 0.08
0 6.957 91.5 0.17
0 6.957 92.3 0.28
0 6.957 92.8 0.35
0 6.957 94.1 0.38
0 6.957 96.0 0.39
0 6.957 98.0 0.40
0 6.957 100.0 0.41
0.03 6.971 92.5 0.00
0.03 6.971 93.0 0.13
0.03 6.971 93.2 0.25
0.03 6.971 93.5 0.42
0.03 6.971 94.2 0.52
0.03 6.971 95.3 0.55
0.03 6.971 97.1 0.57
0.03 6.971 98.1 0.58
0.03 6.971 100.0 0.60
0.06 6.957 93.1 0.00
0.06 6.957 93.7 0.16
0.06 6.957 94.0 0.32
0.06 6.957 94.2 0.48
0.06 6.957 94.6 0.64
0.06 6.957 96.0 0.72
0.06 6.957 98.0 0.75
0.06 6.957 100.0 0.78
Measurement Method: Four-probe method
"Electrical resistivity was measured with a standard four-contact dc technique whereby reversal of the current direction cancels out thermoelectric voltages. Typical current densities for this measurement were 300 mA/cm2. Temperature was measured to an absolute accuracy of ±0.05 K with a calibrated Pt thermometer which was thermally anchored next to the specimen on the Cu sample holder. Absolute values of the electrical resistivities were determined by geometric measurements of the specimens with an experimental uncertainty of ±10%."

Cautions: Evaluated Data
Digitized data were obtained from Figure 1 of the paper.