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arXiv · 2506.02822

Enhanced quantum phase estimation with $q$-deformed nonideal nonclassical light

Duttatreya·Sanjib Dey
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Abstract

We investigate quantum phase estimation in a Mach-Zehnder interferometer using q-deformed photon states, including q-coherent and q-cat states, which model realistic deviations from ideal light sources. By deriving closed-form photon count likelihoods via the Jordan-Schwinger mapping, we compute the quantum and classical Fisher information and perform Bayesian inference on simulated detector data. Our results show that photon counting remains an optimal measurement strategy even for deformed states, with classical and quantum Fisher information in exact agreement. Furthermore, the phase sensitivity improves with increasing q-deformation, indicating enhanced metrological performance driven by nonclassical photon statistics. These findings highlight the utility of q-deformed states in quantum sensing.

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Duttatreya, Sanjib Dey. 2025-06-03. Enhanced quantum phase estimation with $q$-deformed nonideal nonclassical light. https://doi.org/10.1088/1751-8121%2Fae0b0f

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