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arXiv · 2510.16269

Observation of spatially structured Montgomery effect in free space

Murat Yessenov·Luca Sacchi·Alfonso Palmieri·Layton A. Hall·Ayman F. Abouraddy·Federico Capasso
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Abstract

We report the first direct observation of the spatially structured Montgomery effect, a lensless self-imaging phenomenon that generalizes the Talbot effect to aperiodic structures, unfolding repeated tightly focused spots (~10 $\mu$m) in free space. Using a dynamic optical hologram to discretize radial spatial frequencies, we demonstrate self-imaging at distances ranging from 30 to 100 mm. Our method independently controls the focal spot size and self-imaging period, enabling dynamic three-dimensional light patterns. We also show the arbitrary tunability of the transverse profile by demonstrating revivals of Laguerre-Gaussian, Hermite-Gaussian, Ince-Gaussian modes, and Airy beams. These findings open opportunities for multi-plane microscopy, optical atom traps, and quantum atomic systems.

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Murat Yessenov, Luca Sacchi, Alfonso Palmieri, Layton A. Hall, Ayman F. Abouraddy, Federico Capasso. 2025-10-17. Observation of spatially structured Montgomery effect in free space. https://arxiv.org/abs/2510.16269

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