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arXiv · 2204.10500

Josephson junctions of Weyl semimetal $\text{WTe}_2$ induced by spontaneous nucleation of $\text{PdTe}$ superconductor

Manabu Ohtomo·Russell S. Deacon·Masayuki Hosoda·Naoki Fushimi·Hirokazu Hosoi·Michael D. Randle·Mari Ohfuchi·Kenichi Kawaguchi·Koji Ishibashi·Shintaro Sato
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Abstract

We report on the fabrication of Josephson junction devices with weak links utilizing the Weyl and higher-order topological semimetal $\text{WTe}_2$. We show that $\text{WTe}_2\text{/Pd}$ contact annealed at a low temperature of 80°C did not exhibit superconducting properties because neither $\text{WTe}_2$ nor Pd are superconductors in the ground state. Upon 180°C annealing, spontaneous formation of superconducting $\text{PdTe}$ due to Pd diffusion enabled us to obtain the interface between $\text{WTe}_2$ and superconductor suitable for the Josephson junction. This result is a facile technique to make a Josephson junction and induce Cooper pairs into topological telluride semimetals.

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Manabu Ohtomo, Russell S. Deacon, Masayuki Hosoda, Naoki Fushimi, Hirokazu Hosoi, Michael D. Randle, Mari Ohfuchi, Kenichi Kawaguchi, Koji Ishibashi, Shintaro Sato. 2022-04-22. Josephson junctions of Weyl semimetal $\text{WTe}_2$ induced by spontaneous nucleation of $\text{PdTe}$ superconductor. https://doi.org/10.35848/1882-0786%2Fac75a8

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