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arXiv · 2508.08223

Photon Statistics for Fock and Coherent States Interfering in a Beamsplitter

Jhordan A. T. Santiago
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Abstract

We present a straightforward yet comprehensive theoretical study of different quantum states emerging from a bi-modal beamsplitter when various input states interfere. Specifically, we analyze the output states for different combinations of input fields, including Fock states $|n\rangle|m\rangle$, hybrid states $|n\rangle|\alpha\rangle$, and coherent states $|\alpha\rangle|\beta\rangle$. We derive explicit expressions for the output state vectors, calculate the mean photon number, photon number variance, Mandel Q parameter, and secondorder coherence function to characterize the statistical properties of the output fields. Our results are intended as a pedagogical resource, serving as an introductory reference for students and researchers aiming to understand basic photon statistics using beamsplitters.

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Jhordan A. T. Santiago. 2025-08-11. Photon Statistics for Fock and Coherent States Interfering in a Beamsplitter. https://doi.org/10.1590/1806-9126-rbef-2025-0368

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