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arXiv · 2501.14033

Hierarchies of quantum non-Gaussian coherences for bosonic systems: A theoretical study

Lukáš Lachman·Beate E. Asenbeck·Ambroise Boyer·Priyanka Giri·Alban Urvoy·Julien Laurat·Radim Filip
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Abstract

Quantum coherence in bosonic systems is a fundamental resource for quantum technology applications. In this work, we introduce a framework for analyzing coherence in the Fock-state basis, utilizing context-dependent certification to reveal the quantum non-Gaussian nature of the tested coherence. Rather than relying on global coherence measures, our approach targets specific aspects of coherence, enabling a tailored hierarchical classification. We derive and compare two distinct hierarchies, each representing a different context for coherence in bosonic systems. Motivated by current advancements in optical quantum state engineering, we assess the feasibility and depth of these hierarchies under conditions of loss and thermal noise. The methodology introduced here is versatile and can be extended to multi-state and multi-mode coherences, making it adaptable to a wide range of experimental scenarios and platforms.

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Lukáš Lachman, Beate E. Asenbeck, Ambroise Boyer, Priyanka Giri, Alban Urvoy, Julien Laurat, Radim Filip. 2025-01-23. Hierarchies of quantum non-Gaussian coherences for bosonic systems: A theoretical study. https://doi.org/10.1103/t5c6-byhh

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