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arXiv · 2404.00496

Reducing of the Uncertainty Product of Coherent Light through Multi-Photon Interference

Sangbae Kim·Joachim Stohr·Fabian Rotermund·Byoung S. Ham
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Abstract

We demonstrate theoretically and experimentally how the diffraction and interferometric resolution limit for single-mode coherent cw laser light can be overcome by multi-photon interference. By use of a Mach-Zehnder interferometer, operated in the single input and single or double output port geometries, we observe a fringe width reduction of the conventional interference pattern, predicted by the wave or single photon quantum theory, by a factor of up to $1/\sqrt{2N}$ through coincident detection of $N=2,3,4$ photons. Our scheme does not require squeezed or entangled light to overcome the standard quantum limit and greatly facilitates precision interferometry experiments.

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Sangbae Kim, Joachim Stohr, Fabian Rotermund, Byoung S. Ham. 2024-03-30. Reducing of the Uncertainty Product of Coherent Light through Multi-Photon Interference. https://arxiv.org/abs/2404.00496

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