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arXiv · 2409.12049

Quantum-like nonlinear interferometry with frequency-engineered classical light

Romain Dalidet·Anthony Martin·Grégory Sauder·Laurent Labonté·Sébastien Tanzilli
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Abstract

Quantum interferometry methods exploit quantum resources, such as photonic entanglement, to enhance phase estimation beyond classical limits. Nonlinear optics has served as a workhorse for the generation of entangled photon pairs, ensuring both energy and phase conservation, but at the cost of limited rate and degraded signal-to-noise ratio compared to laser-based interferometry approaches. We present a "quantum-like" nonlinear optical method that reaches super-resolution in single-photon detection regime. This is achieved by replacing photon-pairs by coherent states of light, mimicking quantum properties through classical nonlinear optics processes. Our scheme utilizes two high-brightness lasers. This results in a substantially greater signal-to-noise ratio compared to its quantum counterpart. Such an approach paves the way to significantly reduced acquisition times, providing a pathway to explore signals across a broader range of bandwidth. The need to increase the frequency bandwidth of the quantum sensor significantly motivates the potential applications of this pathway.

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Romain Dalidet, Anthony Martin, Grégory Sauder, Laurent Labonté, Sébastien Tanzilli. 2024-09-18. Quantum-like nonlinear interferometry with frequency-engineered classical light. https://doi.org/10.1038/s41598-025-09533-7

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