Silicon technology for novel semiconductor-superconductor hybrid qubits
The quantum information revolution aims at transforming information technology by engineering quantum systems, i.e. qubits, that can be used for quantum information processing (QIP), which allows to perform computations inaccessible to classical computers. In the quest for such systems, solid-state qubits alongside trapped ions currently are the leading candidates. One of the most advanced solid-state technologies to date is based on superconducting quantum circuits (SQCs), which makes use of Josephson tunnel junctions and their macroscopic quantum coherence between two superconducting islands. Due to recent advances in semiconductor-superconductor hybrid (SSH) devices, novel SSH-based qubit architectures have emerged, demonstrating improved properties compared to conventional SQCs, such as in-situ tunability while not being susceptible to flux noise. These novel SSH qubits make use of the true microscopic particle transport within SSH weak links. The main goal of the project is to unambiguously demonstrate SSH-based qubits as a viable and scalable platform for QIP by combining novel SQCs with advanced silicon-technology. The fellow will develop and characterise SSH weak links solely based on silicon (Si), which have the advantage of being fully CMOS compatible and consisting entirely of crystalline materials. Finally, these Si-based weak links will be implemented in novel SQCs, which will combine the good controllability of SQCs with the unique material quality of Si. This will allow the study of the underlying charge dynamics, giving insight into sources of loss, and offer new possibilities for complex architectures. The successful completion of this project will be a decisive landmark towards understanding and integrating such devices in larger circuits, which will be crucial a step towards a vital roadmap for their application in QIP.