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arXiv · 2101.05817

Bias in error-corrected quantum sensing

Ivan Rojkov·David Layden·Paola Cappellaro·Jonathan Home·Florentin Reiter
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Abstract

The sensitivity afforded by quantum sensors is limited by decoherence. Quantum error correction (QEC) can enhance sensitivity by suppressing decoherence, but it has a side-effect: it biases a sensor's output in realistic settings. If unaccounted for, this bias can systematically reduce a sensor's performance in experiment, and also give misleading values for the minimum detectable signal in theory. We analyze this effect in the experimentally-motivated setting of continuous-time QEC, showing both how one can remedy it, and how incorrect results can arise when one does not.

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Ivan Rojkov, David Layden, Paola Cappellaro, Jonathan Home, Florentin Reiter. 2021-12-21. Bias in error-corrected quantum sensing. https://doi.org/10.1103/physrevlett.128.140503

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