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arXiv · 2207.12960

Projective measurements can probe non-classical work extraction and time-correlations

Santiago Hernández-Gómez·Stefano Gherardini·Alessio Belenchia·Matteo Lostaglio·Amikam Levy·Nicole Fabbri
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Abstract

We demonstrate an experimental technique to characterize genuinely nonclassical multi-time correlations using projective measurements with no ancillae. We implement the scheme in a nitrogen-vacancy center in diamond undergoing a unitary quantum work protocol. We reconstruct quantum-mechanical time correlations encoded in the Margenau-Hills quasiprobabilities. We observe work extraction peaks five times those of sequential projective energy measurement schemes and in violation of newly-derived stochastic bounds. We interpret the phenomenon via anomalous energy exchanges due to the underlying negativity of the quasiprobability distribution.

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Santiago Hernández-Gómez, Stefano Gherardini, Alessio Belenchia, Matteo Lostaglio, Amikam Levy, Nicole Fabbri. 2022-07-26. Projective measurements can probe non-classical work extraction and time-correlations. https://doi.org/10.1103/physrevresearch.6.023280

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