Dynamical Decoupling using Universal Optimal Tracking

Amit Devra; Emanuel Malvetti; Niklas J. Glaser; Abhishek Agarwal; Ivan Rungger; Santana Lujan; Max Werninghaus; Stefan Filipp; Leo Van Damme; Steffen J. Glaser

arXiv · 2606.21762

Dynamical Decoupling using Universal Optimal Tracking

Amit Devra·Emanuel Malvetti·Niklas J. Glaser·Abhishek Agarwal·Ivan Rungger·Santana Lujan·Max Werninghaus·Stefan Filipp·Leo Van Damme·Steffen J. Glaser

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Abstract

Dynamical decoupling (DD) is a widely used and resource-efficient technique for error suppression, but conventional DD relies on periodically repeating a short pulse block to refocus the qubit state during idle periods. Imperfections in this block cause residual errors to accumulate, ultimately degrading state recovery over long idle times. Here, we introduce a universal optimal tracking approach that extends the original tracking concept to a fully state-independent setting for designing DD sequences. By monitoring the qubit's evolution at predefined waypoints during optimization, the method dynamically compensates residual errors while preserving regular refocusing. Experimental demonstrations on a superconducting-qubit platform confirm the suppression of error accumulation under static control imperfections, in agreement with numerical predictions. Complementary simulations further show that optimal-tracking-based sequences maintain strong performance under time-dependent noise. These results establish optimal tracking as a practical and hardware-agnostic approach to designing short, robust DD sequences suitable for noisy quantum devices.

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BibTeX RIS

Amit Devra, Emanuel Malvetti, Niklas J. Glaser, Abhishek Agarwal, Ivan Rungger, Santana Lujan, Max Werninghaus, Stefan Filipp, Leo Van Damme, Steffen J. Glaser. 2026-06-19. Dynamical Decoupling using Universal Optimal Tracking. https://arxiv.org/abs/2606.21762

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