In an ultra-high vacuum environment, superconducting thin films are first grown, immediately followed by in situ high-quality encapsulation layers growth. Using photolithography and electron-beam lithography, we fabricate novel Fluxonium superconducting qubits, achieving energy relaxation times (T1) up to 3 ms, approaching the world record.

High-quality thin-film encapsulated superconducting materials retain their intrinsic superconductivity and resist oxidation. Using our photolithography process, microwave planar resonators achieve quality factors above one million, stable for over 14 months, whereas unencapsulated resonators drop by an order of magnitude within two weeks, demonstrating a major breakthrough in long-term superconducting performance.

The high-quality superconducting thin films produced by this technology can fabricate highly coherent qubit chips, advancing the quantum information industry, while also offering potential applications in microwave device fabrication and wireless communication networks.