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arXiv · 1001.3615

Josephson junction in cobalt-doped BaFe2As2 epitaxial thin films on (La, Sr)(Al, Ta)O3 bicrystal substrates

Takayoshi Katase·Yoshihiro Ishimaru·Akira Tsukamoto·Hidenori Hiramatsu·Toshio Kamiya·Keiichi Tanabe·Hideo Hosono
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Abstract

Josephson junctions were fabricated in epitaxial films of cobalt-doped BaFe2As2 on [001]-tilt (La,Sr)(Al,Ta)O3 bicrystal substrates. 10m-wide microbridges spanning a 30-degrees-tilted bicrystal grain boundary (BGB bridge) exhibited resistively-shunted-junction (RSJ)-like current-voltage characteristics up to 17 K, and the critical current was suppressed remarkably by a magnetic field. Microbridges without a BGB did not show the RSJ-like behavior, and their critical current densities were 20 times larger than those of BGB bridges, confirming BGB bridges display a Josephson effect originating from weakly-linked BGB.

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Takayoshi Katase, Yoshihiro Ishimaru, Akira Tsukamoto, Hidenori Hiramatsu, Toshio Kamiya, Keiichi Tanabe, Hideo Hosono. 2010-04-11. Josephson junction in cobalt-doped BaFe2As2 epitaxial thin films on (La, Sr)(Al, Ta)O3 bicrystal substrates. https://doi.org/10.1063/1.3371814

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