Composition dependence of superconducting properties in Bi2(Sr1 - xCax)n + 1CunOy (n=2, 3) thin films
Abstract
Thin films of the Bi2(Sr1-xCax)n+1CunOy (n=2, 3) system were prepared on (100)MgO substrates by coevaporation of Bi2O3, Sr-Ca alloy, and Cu metal. The lattice constant of the c axis of the low Tc (∼85 K) phase (n=2) decreased with increasing Ca composition x. The superconducting transition temperatures of both the low Tc phase and high Tc (∼110 K) phase (n=3) decreased with increasing x. These tendencies indicated that both the low Tc phase and the high Tc phase have a mutual solubility between Ca and Sr atoms in this Bi system and that the Tc 's of these two phases are related to the c-axis lattice constant.
- Publication:
-
Applied Physics Letters
- Pub Date:
- September 1988
- DOI:
- 10.1063/1.100668
- Bibcode:
- 1988ApPhL..53.1213S
- Keywords:
-
- Bismuth Oxides;
- Chemical Composition;
- Copper Oxides;
- High Temperature Superconductors;
- Mixed Oxides;
- Superconducting Films;
- Thin Films;
- Calcium Oxides;
- Crystal Lattices;
- Magnesium Oxides;
- Strontium Compounds;
- Solid-State Physics