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arXiv · 2507.06462

Controlling quantum entanglement with classical non-separable light

R. F. Barros·A. L. S. Santos Junior·A. Z. Khoury·R. Fickler
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Abstract

Here we investigate the quantum frequency conversion of entangled photons driven by a classically non-separable laser beam. We show that the frequency conversion dynamics is described by a quantum channel that stems from the classical drive field through the channel-state duality - the quantum channel is dual to the classical coherence matrix of the drive field. This implies that the evolution of entanglement in the conversion process is bound by the classical non-separability of the drive field, a result that we confirm experimentally. Furthermore, we show that the conversion dynamics can be understood as a swapping operation between classical non-separability and entanglement, unveiling a physical connection between two fundamentally different concepts.

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R. F. Barros, A. L. S. Santos Junior, A. Z. Khoury, R. Fickler. 2025-07-09. Controlling quantum entanglement with classical non-separable light. https://arxiv.org/abs/2507.06462

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