摘要
We have measured the resistivity as a function of temperature in a magnetic field at various field angles θ for oxygen-deficient YBCO films and ultrathin YBCO films; θ is the angle between the crystal c axis and the direction of the magnetic field. The angular dependence of the critical field, Hc2, shows a cusplike behaviour at θ=90° for the oxygen-deficient 60 K YBCO films indicating that the Cu-O2 layers are two-dimensional in nature. Both Tc versus θ in a constant field and Hc2 as a function of θ show a plateau at θ=90° for 83 K (zero resistance) ultrathin YBCO films with a thickness of 20 units of the YBCO cell; these results indicate that there is a coupling between the Cu-O2 layers. The dimensionality of the Cu-O2 layers in oxygen-deficient YBCO films and ultrathin YBCO films is discussed in terms of the anisotropic Ginzburg-Landau model and the Tinkham thin-film model.
原文 | 英語 |
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頁(從 - 到) | 467-473 |
頁數 | 7 |
期刊 | Journal of Low Temperature Physics |
卷 | 90 |
發行號 | 5-6 |
DOIs | |
出版狀態 | 已發佈 - 1993 3月 |
ASJC Scopus subject areas
- 原子與分子物理與光學
- 一般材料科學
- 凝聚態物理學