QSE Quantum Seminar: "High-coherence foundry-compatible superconducting qubit platform"

Please join us for the QSE Center Quantum Seminar with Anton Potočnik from imec who will give a talk about "High-coherence foundry-compatible superconducting qubit platform" on Friday September 11th from 12:00 to 13:30.
Location: 

Pizzas will be available at 12:00. All PhDs, postdocs, students, group leaders, and PIs are welcome to join us.

TITLE: "High-coherence foundry-compatible superconducting qubit platform" 

ABSTRACT: 
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], oxide removal [6,7] and materials such as a-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).

BIO:
Anton Potočnik is a senior researcher at imec, where he develops next-generation technologies for quantum computing applications. His research focuses on identifying and mitigating sources of qubit decoherence, interfacing qubits with cryogenic CMOS electronics, and advancing novel integration strategies to enable scalable quantum processors. He is the recipient of a European Research Council (ERC) grant, supporting his work on pushing the limits of cryo-CMOS operation at millikelvin temperatures for quantum computing. Prior to joining imec, Anton was a postdoctoral researcher at ETH Zurich in Prof. Andreas Wallraff’s group, where he worked on analog quantum simulation, including superconducting-qubit models of photosynthetic processes. He received his PhD in physics from the University of Ljubljana, with research focused on exotic superconductivity in organic superconductors under the mentorship of prof. Denis Arčon.