Aluminum air bridges for superconducting quantum devices realized using a single step electron-beam lithography process

作者：N. Janzen, Michal Kononenko, S. Ren, Adrian Lupaşcu · 发表于：arXiv (Cornell University) · 年份：2022 · DOI：10.1063/5.0103165 · 被引用次数：14 · 研究领域：Quantum and electron transport phenomena、Quantum Information and Cryptography、Physics of Superconductivity and Magnetism

In superconducting quantum devices, air bridges enable increased circuit complexity and density as well as mitigate the risk of microwave loss arising from mode mixing. We implement aluminum air bridges using a simple process based on single-step electron-beam gradient exposure. The resulting bridges have sizes ranging from $20~\mu m$ to $100~\mu m$, with a yield exceeding $99~\%$ for lengths up to $36~\mu m$. When used to connect ground planes in coplanar waveguide resonators, the induced loss contributed to the system is negligible, corresponding to a reduction of the quality factor exceeding $1.0\times10^8$ per bridge. The bridge process is compatible with Josephson junctions and allows for the simultaneous creation of low loss bandages between superconducting layers.