Direct writing of high temperature superconducting Josephson junctions using a thermal scanning probe

Ngoc My Hanh Duong; Amanuel M. Berhane; Dave Mitchell; Rifat Ullah; Ting Zhang; He Zhu; Jia Du; Simon K. H. Lam; Emma E. Mitchell; Avi Bendavid

arXiv · 2410.00372

Direct writing of high temperature superconducting Josephson junctions using a thermal scanning probe

Ngoc My Hanh Duong·Amanuel M. Berhane·Dave Mitchell·Rifat Ullah·Ting Zhang·He Zhu·Jia Du·Simon K. H. Lam·Emma E. Mitchell·Avi Bendavid

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Abstract

In this letter, we demonstrate for the first time the creation of Josephson-like superconducting nanojunctions using a thermal scanning probe to directly inscribe weak links into microstrips of YBa2Cu3O7-x (YBCO). Our method effectively reduces the critical current (Ic) over an order of magnitude. The resulting nanobridges exhibit clear evidence of Josephson effects, of SNS-type junctions, as shown by both the DC and AC Josephson effects. This approach provides a novel and flexible method for scaling up quantum mechanical circuits that operate at liquid nitrogen temperatures. Additionally, it offers a promising pathway for modifying properties of the junctions in-situ and post fabrication.

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Ngoc My Hanh Duong, Amanuel M. Berhane, Dave Mitchell, Rifat Ullah, Ting Zhang, He Zhu, Jia Du, Simon K. H. Lam, Emma E. Mitchell, Avi Bendavid. 2024-10-01. Direct writing of high temperature superconducting Josephson junctions using a thermal scanning probe. https://arxiv.org/abs/2410.00372

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