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arXiv · 2303.05872

Diamond-shaped evolution of the superconducting interference pattern in NbTiN weak-link Josephson junctions

Kui Zhao·Jianfei Xiao·Huaiyuan Liu·Linfeng Tu·Yiwen Ma·Jiangbo He·Mingli Liu·Ruiyang Jiang·Zhongmou Jia·Shang Zhu·Yunteng Shi·Zhaozheng Lyu·Jie Shen·Guangtong Liu·Li Lu·Fanming Qu
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Abstract

The application of in-plane magnetic fields to Josephson junctions enables fundamental exploration of quantum phenomena, including Zeeman-driven 0-$π$ transitions and planar topological superconductivity. However, intrinsic orbital effects arising from nanoscale rippled geometries in practical devices can dominate phase interference signatures, complicating their interpretation. Here, we experimentally probe superconducting interference in NbTiN weak-link Josephson junctions under combined perpendicular and in-plane magnetic fields. The critical supercurrent reveals a distinct diamond-shaped interference pattern, with nodes progressively opening and evolving into V-shaped features, reminiscent of suppression-recovery patterns associated with 0-$π$ transitions. We theoretically analyze the interplay between orbital effects from rippled geometries and non-uniform supercurrent density distributions, demonstrating that their synergistic interaction could reproduce the experimentally observed interference evolution. Our findings elucidate how geometric imperfections and current inhomogeneity cooperatively reshape phase interference, providing critical insights into orbital-dominated phenomena in Josephson systems.

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Kui Zhao, Jianfei Xiao, Huaiyuan Liu, Linfeng Tu, Yiwen Ma, Jiangbo He, Mingli Liu, Ruiyang Jiang, Zhongmou Jia, Shang Zhu, Yunteng Shi, Zhaozheng Lyu, Jie Shen, Guangtong Liu, Li Lu, Fanming Qu. 2025-06-19. Diamond-shaped evolution of the superconducting interference pattern in NbTiN weak-link Josephson junctions. https://doi.org/10.1088/1361-648x%2Faddd56

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