High-temperature superconducting edge junctions with modified interface barriers
This paper summarizes our recent investigations on the fabrication process, microstructure, and characteristics of high-temperature superconducting edge-type Josephson junctions with modified interface barriers. The junctions were fabricated by an in situedge fabrication process using an epitaxial insulator layer as an etching mask. The barriers were formed not by intentional deposition but by interface modification. The modified interface barrier material was identified as a Ba-based perovskite: Ba(Y1-xCux)Oy. The junctions showed resistively and capacitively shunted junction-like current-voltage characteristics and excellent uniformity. 100 junctions showed a spread in the critical current as low as 1= 8% at 4.2 K and the junction characteristics remained the same after a high-temperature process at about 700 °C.
Document Type: Miscellaneous
Fundamental Research Laboratories, NEC Corporation, 34 Miyukigaoka, Tsukuba, Ibaraki 305-8501, Japan
Superconductivity Research Laboratory, ISTEC, 10-13, Shinonome 1, Koto-ku, Tokyo 135-0062, Japan
Publication date: January 1, 2000