All-Electrical Control of a Hybrid Electron Spin/Valley Quantum Bit in SOI CMOS Technology

We fabricated quantum dot devices using a standard SOI CMOS process flow and demonstrated that the spin of confined electrons could be controlled via a local electrical-field excitation, owing to intervalley spin–orbit coupling. We discuss that modulating the confinement geometry via an additional electrode may enable switching a quantum bit (qubit) between an electrically addressable valley configuration and a protected spin configuration. This proposed scheme bears relevance to improve the tradeoff between fast operations and slow decoherence for quantum computing on a Si qubit platform. Finally, we evoke the impact of process-induced variability on the operating bias range.