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arXiv · 2507.06879

Impact of Polarization Distinguishability on Coherence in QIUP

Gaytri Arya·Paolo Bianchini·Alberto Diaspro
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Abstract

Quantum imaging with undetected photons (QIUP) is a promising technique for non-invasive imaging, particularly at wavelengths where detectors are inefficient or unavailable. Recent studies have investigated the role of polarization in QIUP schemes. In this work, we examine whether post-generation optical elements can recover interference when the signal photons are distinguishable in polarization at the source. Specifically, we employ a Mach-Zehnder interferometer after the photon pairs are generated from two nonlinear crystals. Our results indicate that polarization distinguishability at the time of generation leads to a loss of interference that cannot be restored by post-generation optical arrangements. This highlights the fundamental importance of indistinguishability at the source for maintaining coherence in QIUP systems.

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Gaytri Arya, Paolo Bianchini, Alberto Diaspro. 2025-07-09. Impact of Polarization Distinguishability on Coherence in QIUP. https://arxiv.org/abs/2507.06879

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