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arXiv · 2410.18783

Run-and-tumble exact work statistics in a lazy quantum measurement engine: stochastic information processing

Léa Bresque·Debraj Das·Édgar Roldán
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Abstract

We introduce a single-qubit quantum measurement engine fuelled by backaction energy input. To reduce energetic costs associated with information processing, the measurement outcomes are only used with a prescribed laziness probability in the feedback step. As a result, we show that the work extracted over consecutive cycles is a second-order Markov process, analogous to a run-and-tumble process with transient anomalous diffusion. We derive exact analytical expressions for the work finite-time moments and first-passage-time statistics. Furthermore, we find the optimal laziness probability maximizing the mean power extracted per cycle.

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Léa Bresque, Debraj Das, Édgar Roldán. 2024-10-24. Run-and-tumble exact work statistics in a lazy quantum measurement engine: stochastic information processing. https://doi.org/10.1103/physrevlett.134.200402

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