Silicon qubit fidelities approaching stochastic noise limits via pulse optimisation

To achieve a fault-tolerant quantum computing system, it will be necessary to further improve single qubit gate fidelities to reduce the overhead for quantum computing. In this talk, we show that by employing GRAPE computed optimised control pulse shaping scheme and other calibration techniques, we can improve average Clifford gate fidelities for silicon quantum dot spin qubits by an order of magnitude, to 99.96% (equivalent coherence time of 9.4ms) experimentally, the highest up to date record in silicon quantum dot qubits. Additionally, we confirm that the shaped pulse scheme works by suppressing most non-Markovian noise with combined unitarity measurement.