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arXiv · 2102.01327

Experimental characterisation of a non-Markovian quantum process

K. Goswami·C. Giarmatzi·C. Monterola·S. Shrapnel·J. Romero·F. Costa
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Abstract

Every quantum system is coupled to an environment. Such system-environment interaction leads to temporal correlation between quantum operations at different times, resulting in non-Markovian noise. In principle, a full characterisation of non-Markovian noise requires tomography of a multi-time processes matrix, which is both computationally and experimentally demanding. In this paper, we propose a more efficient solution. We employ machine learning models to estimate the amount of non-Markovianity, as quantified by an information-theoretic measure, with tomographically incomplete measurement. We test our model on a quantum optical experiment, and we are able to predict the non-Markovianity measure with $90\%$ accuracy. Our experiment paves the way for efficient detection of non-Markovian noise appearing in large scale quantum computers.

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K. Goswami, C. Giarmatzi, C. Monterola, S. Shrapnel, J. Romero, F. Costa. 2021-02-02. Experimental characterisation of a non-Markovian quantum process. https://doi.org/10.1103/physreva.104.022432

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