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arXiv · 2504.20399

Petz recovery maps of single-qubit decoherence channels in an ion trap quantum processor

Wen-Han Png·Valerio Scarani
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Abstract

The Petz recovery map provides a near-optimal reversal of quantum noise, yet proposals for its implementation are only recent. We propose a physical realization of the exact state-specific Petz map in an ion trap for qubit decoherence channels. Our circuit constructions require at most $1 (2)$ ancilla qubits and $3 (20)$ CNOT gates for channels with Kraus rank $2 (>2)$. We analyze typical ion trap errors and construct corresponding Petz maps, simulating their performance under realistic noise modeled by residual spin-motion coupling. Quantum circuits are provided for depolarizing, dephasing, and amplitude damping channels. Focusing on single-shot recovery, suited for present-day devices, we also quantify the precision of prior knowledge required to achieve a recovery error below 0.01 across varying decoherence levels and state purities.

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Wen-Han Png, Valerio Scarani. 2025-04-29. Petz recovery maps of single-qubit decoherence channels in an ion trap quantum processor. https://doi.org/10.1103/7f8x-n2np

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