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arXiv · 2506.15820

Parallelized projective measurements for spatial photonic qudits estimation

Quimey Pears Stefano·Lorena Rebón·Claudio Iemmi
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Abstract

We present a quantum state tomography method that enables the reconstruction of \emph{arbitrary} $d-$dimensional quantum states encoded in the discretized transverse momentum of photons, by using \emph{only} $d+1$ experimental settings. To this end, we identify a family of bases with the property that the outcomes of a projective measurement are \emph{spatially multiplexed} on the interference pattern of the projected state. Using the proposed scheme we performed, as a proof-of-principle, an experimental reconstruction of $d=6-$dimensional states, for which a complete set of mutually unbiased bases does not exist. We obtained fidelity values above 0.97 for both pure and mixed states, reducing the number of experimental settings from $42$ to only $7$.

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Quimey Pears Stefano, Lorena Rebón, Claudio Iemmi. 2025-06-18. Parallelized projective measurements for spatial photonic qudits estimation. https://arxiv.org/abs/2506.15820

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