Robust generation of $N$-partite $N$-level singlet states by identical particle interferometry

Matteo Piccolini; Marcin Karczewski; Andreas Winter; Rosario Lo Franco

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arXiv · 2312.17184

Robust generation of $N$-partite $N$-level singlet states by identical particle interferometry

Matteo Piccolini·Marcin Karczewski·Andreas Winter·Rosario Lo Franco

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Abstract

We propose an interferometric scheme for generating the totally antisymmetric state of $N$ identical bosons with $N$ internal levels (generalized singlet). This state is a resource for various problems with dramatic quantum advantage. The procedure uses a sequence of Fourier multi-ports, combined with coincidence measurements filtering the results. Successful preparation of the generalized singlet is confirmed when the $N$ particles of the input state stay separate (anti-bunch) on each multiport. The scheme is robust to local lossless noise and works even with a totally mixed input state.

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Matteo Piccolini, Marcin Karczewski, Andreas Winter, Rosario Lo Franco. 2023-12-28. Robust generation of $N$-partite $N$-level singlet states by identical particle interferometry. https://arxiv.org/abs/2312.17184

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