Homointerface planar Josephson junction based on inverse proximity effect

• Main Authors: Fan, Juewen, Jiang, Bingyan, Zhao, Jiaji, Bi, Ran, Zhou, Jiadong, Liu, Zheng, Kang, Ning, Qu, Fanming, Lu, Li, Wu, Xiaosong
• Other Authors: School of Materials Science and Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Materials; Josephson Junction Devices; Superconducting Films
• Online Access: https://hdl.handle.net/10356/161242
• Institution: Nanyang Technological University

The quality of a superconductor-normal metal-superconductor Josephson junction (JJ) depends crucially on the transparency of the superconductor-normal metal (S/N) interface. We demonstrate a technique for fabricating planar JJs with perfect S/N interfaces. The technique utilizes a strong inverse proximity effect discovered in Al/V$_5$S$_8$ bilayers, by which the Al layer is driven into the resistive state. The highly transparent S/N homointerface and the peculiar normal metal enable the flow of Josephson supercurrent across a 2.9 $\mu$m long weak link. Moreover, our JJ exhibits a giant critical current and a large product of the critical current and the normal state resistance.