Method synthesises quantum controls in tens of milliseconds.

Researchers led by Eduardo Willwock Lussi obtained a mean local optimization time of 39.945 ms per gate after preparation of the interpolation base. This automated, semi-analytical approach dramatically reduces the time needed to create high-fidelity quantum gates, a process that typically requires minutes using existing numerical optimization techniques. The team’s work, based on the Space Curve Quantum Control formalism, designs control pulses robust against both amplitude and dephasing errors. By mapping quantum evolution onto a geometric space curve and employing the Pontryagin Maximum Principle, the method achieved nominal gate infidelities under 10-9 after virtual phase correction. The Space Curve Quantum Control (SCQC) formalism offers a geometric approach to designing quantum gates, representing single-qubit dynamics as a space curve where geometric constraints directly influence robustness to control errors. This method builds on earlier work extending SCQC to multiqubit systems and incorporating multiple independent noise sources, offering a distinct…