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arXiv · 2405.04090

Protecting quantum gates from arbitrary single- and two-qubit errors

Chunfeng Wu·Gangcheng Wang·Xun-Li Feng
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Abstract

We explore the protection of quantum gates from arbitrary single- and two-qubit noises with properly designed dynamical decoupling pulses. The proposed dynamical decoupling method is a concatenation of a sequence of pulses formed by $σ_x$, $σ_xσ_x$ with another sequence constructed by $σ_z$, $σ_zσ_z$. The concatenation of the two sequences results in desired pulses to fight agianst any single- and two-qubit errors. The success of our method relies on the ability to adjust system parameters or interaction terms, which can be achieved in different physical systems, including trapped ions and superconducting qubits. We finally explore the performance of our method numerically with the above-mentioned errors that are changing at any moment and show the preferred protection offered by the method. Therefore, our method is a timely step forward in preserving quantum gates at the level of physical qubits.

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Chunfeng Wu, Gangcheng Wang, Xun-Li Feng. 2024-05-07. Protecting quantum gates from arbitrary single- and two-qubit errors. https://arxiv.org/abs/2405.04090

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