Optimized mitigation of random-telegraph-noise dephasing by spectator-qubit sensing and control
Hongting Song, Areeya Chantasri, Behnam Tonekaboni, Howard M. Wiseman · Physical Review A · 2023
Spectator qubits (SQs) have been proposed as a way to estimate, and thus mitigate, the effect of time-varying noise in hard-to-access data qubits. Using optimal control theory, this Letter shows that a single SQ suffices to suppress the decoherence from a common type of noise in quantum devices by an amount quadratic in the SQ sensitivity.