From Field Effect Transistors to Spin Qubits: Focus on Group IV Materials, Architectures and Fabrications.

In this review, we focus on group IV one-dimensional devices for quantum technology. We outline the foundational principles of quantum computing before delving into materials, architectures and fabrication routes, separately, by comparing the bottom-up and top-down approaches. We demonstrate that due to easily tunable composition and crystal/interface quality and relatively less demanding fabrications, the study of grown nanowires such as core-shell Ge-Si and Ge hut wires has created a very fruitful field for studying unique and foundational quantum phenomena. We discuss in detail how these advancements have set the foundations and furthered realization of SETs and qubit devices with their specific operational characteristics. On the other hand, top-down processed devices, mainly as Si fin/nanowire field-effect transistor (FET) architectures, showed their potential for scaling up the number of qubits while providing ways for very large-scale integration (VLSI) and co-integration with conventional CMOS. In all cases we compare the fin/nanowire qubit architectures to other closely related approaches such as planar (2D) or III-V qubit platforms, aiming to highlight the cutting-edge benefits of using group IV one-dimensional morphologies for quantum computing. Another aim is to provide an informative pedagogical perspective on common fabrication challenges and links between common FET device processing and qubit device architectures.