Tuning multiple single-hole spin qubit in silicon above fault tolerant threshol

Hole-spin qubits hosted by quantum dots in group-IV semiconductors are very promising candidates for large-scale quantum computing. Measuring single hole spin qubit in Si-MOS devices, we have recently demonstrated that they exhibit regions of insensitivity to charge noise called ‘’sweetlines’’. Remarquably, such regions show increased driving efficiency, and exhibit record-breaking Rabi quality factors up to 1200.

Leveraging on the electric dependence of the sweetline position, we present here their alignment in multiple qubits hosted in a natural silicon nanowire device. In this configuration, we performed randomized benchmarking experiments on both qubits individually, achieving fidelities well above 99%, even with qubits living in noisy electric and magnetic environment.