Agenda

High-coherence foundry-compatible superconducting qubit platform

Anton Potočnik (IMEC, Belgium)

Date/Horaire : le mardi 17 février 2026 à 14h00

Lieu : Salle Rémy Lemaire K223, Institut Néel

Résumé : The field of superconducting qubit technology has experienced rapid development over the past two decades. Recent advancements in the fabrication, control and measurement of superconducting quantum devices have enabled integration of hundreds of qubits on a single chip. However, the path towards larger-scale integration of thousands of qubits on a chip remains unclear. This talk presents imec’s platform for scalable superconducting qubit fabrication, which is based on foundry-compatible thin film processing 1 and overlay Josephson-junction fabrication 2. The platform enables all-optical superconducting transmon qubit fabrication on 300 mm wafers, achieving near state-of-the-art coherence times, record-low aging and comparable Josephson junction variability to standard shadow-evaporation technique 3. A key focus of this presentation will be the understanding and mitigation of microwave losses induced by various fabricaiton steps such as Ar-milling 4 and oxide removal 6,7 and materials such as -Ta 5 or ultra-high-resistivity silicon. The talk will conclude with an outline of ongoing efforts toward large-scale qubit characterization and control using cryo-CMOS electronics operating near qubits at the mixing-chamber plate of a dilution refrigerator 8. 1 Mongillo, et al., IEDM (2022). 2 Verjauw et al., npj Quantum Information 8, 93 (2022). 3 Van Damme, et al., Nature, 634, 74 (2024). 4 Van Damme, et al., PRA 20, 014034 (2023). 5 Lozano, et al. Mater. Quantum. Technol. 4, 025801 (2024). 6 Verjauw, et al., PRA 16, 014018 (2021). 7 Lozano, et al., Advanced Science 12, e09244 (2025). 8 Acharya, et al., Nature Electronics, 6, 900 (2023).