Advancing Quantum Devices with Germanium: Insights from Transport and Superconducting Hybrid Systems

University of Basel

Quantum transport measurements serve as a cornerstone for understanding material properties and designing next-generation quantum devices. This talk highlights the unique role of germanium (Ge) heterostructures in enabling high quality semiconducting and superconducting devices. First, we explore Ge's suitability for spin qubits, emphasizing the critical role of surface treatments in minimizing interface traps and the use of backgates to tune quantum properties. Next, we delve into superconducting hybrid devices, demonstrating a clean approach approach to proximitize Ge. We showcase a device capable of transitioning from a closed system to a proximitized quantum dot and further to a Josephson junction with a single gate, revealing the rich physics of proximitized systems. Finally, we present high-performance resonators on Ge, validating the potential of Ge in diverse quantum technologies.