Superconducting Hg-Ba-Ca-Cu-O thin films on lanthanum aluminate and sapphire substrates
| Autor: | T. Stelzner, H. Schneidewind, G. Bruchlos |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Superconductivity
High-temperature superconductivity Materials science Condensed matter physics Analytical chemistry Condensed Matter Physics Epitaxy Omega Electronic Optical and Magnetic Materials law.invention chemistry.chemical_compound chemistry Lanthanum aluminate law Sapphire Electrical and Electronic Engineering Thin film Sheet resistance |
| Zdroj: | IEEE Transactions on Appiled Superconductivity. 13:2766-2768 |
| ISSN: | 1051-8223 |
| Popis: | Epitaxial c-axis-oriented HgBa/sub 2/CaCu/sub 2/O/sub 6+/spl delta// (Hg-1212) thin films have been prepared on lanthanum aluminate as well as on CeO/sub 2/ buffered r-plane sapphire substrates using a Tl-Hg cation-exchange process. Films on LaAlO/sub 3/ exhibited superconducting transition temperatures (T/sub c/) up to 122 K and critical current densities in the range of 2.2-3.1 MA/cm/sup 2/ at 77 K and under self-field. For the microwave surface resistance (R/sub s/) values of /spl sim/4 m/spl Omega/ at 17.86 GHz and 77 K have been obtained. In comparison, films on sapphire substrates with T/sub c/ values up to 118 K showed critical current densities in the range of 0.7-1.0 MA/cm/sup 2/ and R/sub s/ values of /spl sim/7 m/spl Omega/. With further optimization of processing an improvement of superconducting properties of Hg-1212 films on sapphire substrates is expected. |
| Databáze: | OpenAIRE |
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