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arXiv · 2211.11451

Decoherence-assisted quantum driving

Pavel Cejnar·Pavel Stránský·Jan Střeleček·Felipe Matus
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Abstract

We propose a protocol for transitionless driving of a bound quantum system in its parameter space using repeated measurement-like interactions with an external spectator system. As a consequence of the quantum Zeno effect, the fidelity of the final state preparation is equal to unity in the limit of infinite-rate interactions. For finite-rate interactions, the maximal fidelity is achieved for the driving trajectory having a minimal geometric length and keeping a constant speed with respect to the Provost-Vallee metric in the parameter space. We numerically test the protocol in an interacting multiqubit system, demonstrating its dominance over the method of coherent driving.

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Pavel Cejnar, Pavel Stránský, Jan Střeleček, Felipe Matus. 2022-11-21. Decoherence-assisted quantum driving. https://doi.org/10.1103/physreva.107.l030603

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