High-fidelity qubit control in a natural Si-MOS quantum dot using a 300 mm silicon on insulator wafer

We demonstrate high-fidelity single qubit control in a natural Si-MOS quantum dot fabricated in an industrial 300 mm wafer process on a silicon on insulator wafer using electron spin resonance. A relatively high optimal Rabi frequency of 5 MHz is achieved, decoupling the electron spin from its 29Si environment. Tracking the qubit frequency reduces the impact of low-frequency noise in the qubit frequency and improves the TRabi from 7 to 11 μs at a Rabi frequency of 5 MHz, resulting in Q-factors exceeding 50. Randomized benchmarking returns an average single gate control fidelity of 99.5±0.3%. As a result of pulse-area calibration, this fidelity is limited by the Rabi Q-factor. These results show that a fast Rabi frequency and a feedback protocol enable high fidelity in these Si-MOS devices, despite the low-frequency magnetic noise.