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arXiv · 2401.15521

Demonstration of monogamy laws for Gaussian steering in optomechanics

J El Qars·M Daoud·R Ahl Laamara·N Habiballah
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Abstract

Secrecy and security are crucial in communication. So, quantum secret sharing protocol has recently been proposed to distribute a secret message to a set of parties, where the decoding procedure is forbidden individually, and a cooperative operation is needed. For this, quantum steering as an intriguing kind of nonlocality, is proven to be a useful resource for efficient implementations of the QSS protocol. Here, we study the distribution of Gaussian steering over an asymmetric three-mode optomechanical state. We show that a single-mode cannot be jointly steered by the two others, and further verify the monogamy inequalities of Gaussian steering. The state at hand displays genuine tripartite steering. Also, we observe one-way steering in the configuration (1vs1) mode as well as (1vs2) mode, hence, we reveal that the asymmetry introduced into the state we consider, is a necessary condition but not sufficient for reaching one way steering. As well, we detect one-way steering between two modes never directly interact. Strikingly, our model exhibits an extreme level of steering, where two single-mode cannot steer individually the third mode, while, they can collectively, which is decisive for practical execution of the QSS protocol.

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J El Qars, M Daoud, R Ahl Laamara, N Habiballah. 2024-01-27. Demonstration of monogamy laws for Gaussian steering in optomechanics. https://doi.org/10.1140/epjp%2Fs13360-020-00120-5

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