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arXiv · 2302.09776

Gate-defined Josephson weak-links in monolayer $\mathrm{WTe_2}$

Michael D. Randle·Masayuki Hosoda·Russell S. Deacon·Manabu Ohtomo·Patrick Zellekens·Kenji Watanabe·Takashi Taniguchi·Shota Okazaki·Takao Sasagawa·Kenichi Kawaguchi·Shintaro Sato·Koji Ishibashi
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Abstract

Systems combining superconductors with topological insulators offer a platform for the study of Majorana bound states and a possible route to realize fault tolerant topological quantum computation. Among the systems being considered in this field, monolayers of tungsten ditelluride ($\mathrm{WTe_2}$) have a rare combination of properties. Notably, it has been demonstrated to be a Quantum Spin Hall Insulator (QSHI) and can easily be gated into a superconducting state. We report measurements on gate-defined Josephson weak-link devices fabricated using monolayer $\mathrm{WTe_2}$. It is found that consideration of the two dimensional superconducting leads are critical in the interpretation of magnetic interference in the resulting junctions. The reported fabrication procedures suggest a facile way to produce further devices from this technically challenging material and the results mark the first step toward realizing versatile all-in-one topological Josephson weak-links using monolayer $\mathrm{WTe_2}$.

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Michael D. Randle, Masayuki Hosoda, Russell S. Deacon, Manabu Ohtomo, Patrick Zellekens, Kenji Watanabe, Takashi Taniguchi, Shota Okazaki, Takao Sasagawa, Kenichi Kawaguchi, Shintaro Sato, Koji Ishibashi. 2023-02-20. Gate-defined Josephson weak-links in monolayer $\mathrm{WTe_2}$. https://doi.org/10.1002/adma.202301683

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