An enlarged view of the YBCO (006) peak is illustrated in FIG. 23. FIG. 23 is an enlarged view of 2XRD-Pr0.00Y1.00BCO+Pr0.22Y0.78BCO—CW near the YBCO (006) peak. Since the intensity of the nearby LAO (200) peak is small, the peak position of this portion will be discussed as the central portion of the half value of the peak intensity. Due to the influence of the LaAlO3 substrate (200) peak, the YBCO (006) peak is observed at 46.68° on the slightly higher angle side by this method. In the evaluation between samples, it is considered that the influence of the LaAlO3 substrate (200) peak does not change significantly unless the position of 2θ deviates from 0.2°, and it seems that relative comparison is possible.
In FIG. 23, the peak of 2XRD-Pr0.00Y1.00BCO+Pr0.22Y0.78BCO—CW is a single line. It is said that the YBCO peaks at (006) at 46.68°, for example, the SmBCO peaks at 46.53°, and the NdBCO peaks at 46.46°. The LaBCO is 46.00°. This is related to lanthanoid contraction, where the c-axis length is longer in La with a large atomic radius, and the (006) peak is located on the low angle side.
If the PrBCO forms the perovskite structure and the valence of Pr does not change, the peak position should appear near 46.2°, which is the central portion of the LaBCO and NdBCO. However, the result in FIG. 23 shows only one peak at 46.746°. This means that the PrBCO and YBCO form a common or single perovskite structure even with a 22% Pr mixture. It indicates that it is single crystal or crystallographically continuous. The peak intensity was 96000 cps, 2θ=46.746°.
