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arXiv · 2501.06393

X-ray microcomputed tomography of 3D chaotic microcavities

Abstract

Chaotic microcavities play a crucial role in several research areas, including the study of unidirectional microlasers, nonlinear optics, sensing, quantum chaos, and non-Hermitian physics. To date, most theoretical and experimental explorations have focused on two-dimensional (2D) chaotic dielectric microcavities, while there have been minimal studies on three-dimensional (3D) ones since precise geometrical information of a 3D microcavity can be difficult to obtain. Here, we image 3D microcavities with submicron resolution using X-ray microcomputed tomography (micro CT), enabling nondestructive imaging that preserves the sample for subsequent use. By analyzing the ray dynamics of a typical deformed microsphere, we demonstrate that a sufficient deformation along all three dimensions can lead to chaotic ray trajectories over extended time scales. Notably, using the X-ray micro CT reconstruction results, the phase space chaotic ray dynamics of a deformed microsphere are accurately established. X-ray micro CT could become a unique platform for the characterization of such deformed 3D microcavities by providing a precise means for determining the degree of deformation necessary for potential applications in ray chaos and quantum chaos.

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Ke Tian, Mohammed Zia Jalaludeen, Yeon Ui Lee, Shilong Li, Sile Nic Chormaic. 2025-11-04. X-ray microcomputed tomography of 3D chaotic microcavities. https://arxiv.org/abs/2501.06393

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