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arXiv · 2301.03909

Metrological detection of entanglement generated by non-Gaussian operations

David Barral·Mathieu Isoard·Giacomo Sorelli·Manuel Gessner·Nicolas Treps·Mattia Walschaers
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Abstract

Entanglement and non-Gaussianity are physical resources that are essential for a large number of quantum-optics protocols. Non-Gaussian entanglement is indispensable for quantum-computing advantage and outperforms its Gaussian counterparts in a number of quantum-information protocols. The characterization of non-Gaussian entanglement is a critical matter as it is in general highly demanding in terms of resources. We propose a simple protocol based on the Fisher information for witnessing entanglement in an important class of non-Gaussian entangled states: photon-subtracted states. We demonstrate that our protocol is relevant for the detection of non-Gaussian entanglement generated by multiple photon-subtraction and that it is experimentally feasible through homodyne detection.

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David Barral, Mathieu Isoard, Giacomo Sorelli, Manuel Gessner, Nicolas Treps, Mattia Walschaers. 2023-01-10. Metrological detection of entanglement generated by non-Gaussian operations. https://arxiv.org/abs/2301.03909

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