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arXiv · 2610.17447

Distributed quantum phase sensing using an SU(1,1) Perelomov coherent state in a Mach-Zehnder interferometer network

Seloua Boulifa·Abdallah Slaoui·Hanane EL Hadfi·Rachid Ahl Laamara
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Abstract

We present a theoretical study of distributed quantum sensing using a reconfigurable network of $N$ Mach--Zehnder interferometers to simultaneously estimate weighted linear combinations of relative phase shifts. The proposed scheme relies on injecting a Perelomov coherent state, generated from the SU(1,1) group representation, into one port of a passive quantum circuit while the remaining modes are initialized in the vacuum state, thereby establishing non-trivial quantum correlations among the sensors. Based on multi-parameter quantum estimation theory, our analysis shows that this entangled strategy outperforms the standard shot-noise limit and asymptotically achieves the Heisenberg limit. Furthermore, we highlight the crucial role of the first beam splitter's asymmetry; specifically, the optimal transmission coefficient that maximizes sensitivity corresponds to its maximum imbalance. Compared to a separable approach utilizing the same total average photon number, the entangled strategy yields a more efficient use of quantum resources, guaranteeing an accuracy gain between $1$ and $N$. This demonstrates that the entangled strategy is systematically superior to its separable counterpart. Ultimately, these results illustrate the potential of entangled distributed quantum sensor networks for high-precision measurements and provide clear guidelines for optimizing interferometric architectures in quantum metrology.

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Seloua Boulifa, Abdallah Slaoui, Hanane EL Hadfi, Rachid Ahl Laamara. 2026-10-12. Distributed quantum phase sensing using an SU(1,1) Perelomov coherent state in a Mach-Zehnder interferometer network. https://doi.org/10.1364/josab.609310

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