Unlocking the Potential of Fluxonium Qubits for Quantum Information Science

Speaker: Prof. Yen-Hsiang Lin (Department of Physics, National Tsing Hua University)

Venue: Room 36173 (1F), Department of Physics, New Science Building

Date & Time: Monday, September 14, 2026 | 12:10 PM

Superconducting qubits have emerged as one of the most promising platforms for quantum computing. Among them, the fluxonium qubit stands out for its long coherence times, large anharmonicity, and reduced sensitivity to noise, making it a promising candidate for scalable quantum processors and quantum-optical applications.
In this talk, I will present our recent efforts to advance fluxonium-based quantum technologies, spanning materials, device fabrication, automated characterization, and quantum optics. I will first discuss our development of high-quality, non-aging superconducting materials and surface-passivation techniques that preserve the quality factors of superconducting microwave resonators for up to 14 months. By incorporating these techniques into qubit fabrication, we have achieved fluxonium energy-relaxation times, T1, as long as 3.3 ms. Toward scaling up device characterization and control, I will introduce our AI-assisted, FPGA-based measurement platform for fast and automated characterization of superconducting qubits. Finally, I will present our recent observation of electromagnetically induced transparency (EIT) in a single fluxonium artificial atom coupled to a microwave waveguide.
These results illustrate how fluxonium can serve not only as a high-coherence computational qubit, but also as a versatile light–matter interface for manipulating microwave photons, opening opportunities for quantum interconnects and quantum networks.