Composite Pulses Beyond Static Noises

Xin Wang

Quantum operations are highly sensitive to environmental noise. Dynamically corrected gates, in particular composite pulse sequences, are traditionally designed by expanding the evolution operator with respect to certain noise parameters and then setting leading orders to zero, which are based on the assumption that noises are static. However, many quantum systems experience time-dependent noise, and generaling existing methods to treat non-static noises have proven difficult. In this talk, we introduce composite pulses designed to mitigate dynamic, non-static noise via a geometric framework. While recovering existing composite pulse sequences, we develop new ones which are shorter, and less prone to time-dependent noises. We demonstrate the effectiveness of our method using 1/f noise. Our method offers improved gate fidelity under complex noise environments, which should be useful for more reliable control in near-term quantum devices.

This work is supported by the Research Grants Council of Hong Kong (CityU 11304920).