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arXiv:2312.16774

The quantum beam splitter with many partially indistinguishable photons: multiphotonic interference and asymptotic classical correspondence

Miguel Villalobos, Alejandra Valencia, Alonso Botero

Published Dec 28, 2023• 0 citations
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Abstract

We present the asymptotic analysis of the quantum two-port interferometer in the $n \rightarrow \infty$ limit of $n$ partially indistinguishable photons. Using the unitary-unitary duality between port and inner-mode degrees of freedom, the probability distribution of output port counts can be decomposed as a sum of contributions from independent channels, each associated to a spin-$j$ representation of $SU(2)$ and, in this context, to $2 j$ effectively indistinguishable photons in the channel. Our main result is that the asymptotic output distribution is dominated by the $O(\sqrt{n})$ channels around a certain $j^*$ that depends on the degree of indistinguishability. The asymptotic form is essentially the doubly-humped semi-classical envelope of the distribution that would arise from $2 j^*$ indistinguishable photons, and which reproduces the corresponding classical intensity distribution.

DOI
10.48550/arxiv.2312.16774

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