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arXiv · 2302.10132

Metrology and multipartite entanglement in measurement-induced phase transition

Giovanni Di Fresco·Bernardo Spagnolo·Davide Valenti·Angelo Carollo
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Abstract

Measurement-induced phase transition arises from the competition between a deterministic quantum evolution and a repeated measurement process. We explore the measurement-induced phase transition through the Quantum Fisher Information in two different metrological scenarios. We demonstrate through the scaling behavior of the quantum Fisher information the transition of the multi-partite entanglement across the phases. In analogy with standard quantum phase transition, we reveal signature of a measurement-induced phase transition in the non-analytic behaviour of the quantum Fisher information as the measurement strength approaches the critical value. Our results offer novel insights into the features of a quantum systems undergoing measurement-induced phase transition and indicate potential avenues for further exploration in the field of quantum physics.

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Giovanni Di Fresco, Bernardo Spagnolo, Davide Valenti, Angelo Carollo. 2023-02-20. Metrology and multipartite entanglement in measurement-induced phase transition. https://doi.org/10.22331/q-2024-04-30-1326

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