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arXiv · 2405.11398

Second-harmonic optical diffraction tomography

Amirhossein Saba·Carlo Gigli·Ye Pu·Demetri Psaltis
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Abstract

Optical diffraction tomography (ODT) has emerged as an important label-free tool in biomedicine to measure the three-dimensional (3D) structure of a biological sample. In this paper, we describe ODT using second-harmonic generation (SHG) which is a coherent nonlinear optical process with a strict symmetry selectivity and has several advantages over traditional fluorescence methods. We report the tomographic retrieval of the 3D second-order nonlinear optical susceptibility using two-dimensional holographic measurements of the SHG fields at different illumination angles and polarization states. The method is a generalization of the conventional linear ODT to the nonlinear scenario. We demonstrate the method with a numerically simulated nanoparticle distribution and an experiment with muscle tissue fibers. Our results show that SHG ODT does not only provide an effective contrast mechanism for label-free imaging but also due to the symmetry requirement enables the visualization of properties that are not otherwise accessible.

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BibTeXRIS

Amirhossein Saba, Carlo Gigli, Ye Pu, Demetri Psaltis. 2024-05-18. Second-harmonic optical diffraction tomography. https://arxiv.org/abs/2405.11398

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