Tuning Methods for Semiconductor Spin Qubits

Recent progress on increasingly complex devices based on semiconductor spin qubits shows that automated methods are indispensable for efficient device characterization and further scale-up. The authors present fast, fully automated procedures to extract key device parameters, as well as various readout and initialization points for operating a two-electron qubit. These efficient, quantitative methods can be the basis for automatic tune-up, in which gate voltages are iteratively adjusted based on the deviation of measured parameters from targets. This would enable operation of devices with more and more qubits, and systematically optimize fabrication procedures.