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arXiv · 1110.1870

Robust Trapped-Ion Quantum Logic Gates by Continuous Dynamical Decoupling

A. Bermudez·P. O. Schmidt·M. B. Plenio·A. Retzker
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Abstract

We introduce a novel scheme that combines phonon-mediated quantum logic gates in trapped ions with the benefits of continuous dynamical decoupling. We demonstrate theoretically that a strong driving of the qubit decouples it from external magnetic-field noise, enhancing the fidelity of two-qubit quantum gates. Moreover, the scheme does not require ground-state cooling, and is inherently robust to undesired ac-Stark shifts. The underlying mechanism can be extended to a variety of other systems where a strong driving protects the quantum coherence of the qubits without compromising the two-qubit couplings.

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A. Bermudez, P. O. Schmidt, M. B. Plenio, A. Retzker. 2012-04-10. Robust Trapped-Ion Quantum Logic Gates by Continuous Dynamical Decoupling. https://doi.org/10.1103/physreva.85.040302

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