Optimization of Si/SiGe Heterostructures for Large and Robust Valley Splitting in Silicon Qubits
This research used a systematic optimization framework to find ideal Germanium (Ge) concentration profiles in Si/SiGe quantum wells to improve valley splitting for silicon qubits. The resulting 'modulated wiggle well' design significantly boosts the deterministic part of the splitting while strongly suppressing disorder-induced variability, allowing for wide electrical tunability from 200 μeV up to 1 meV.