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arXiv · 2608.18750

Seeded SU(1,1) interferometry for Fourier-domain optical coherence tomography

Alejandra A. Padilla·Valentina Gacha·Daniel F. Urrego·Juan P. Torres
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Abstract

We demonstrate Fourier-domain optical coherence tomography (FD-OCT) based on a seeded SU(1,1) interferometer. Multilayer objects are probed with broadband light centered at 1550nm, while depth-resolved 3D images are reconstructed from photon flux measurements centered at 810nm. We show that, in the low parametric-gain regime, seeding increases the photon flux, enabling volumetric imaging with a spectrometer rather than single-photon detectors. Our analysis further shows that, under the conditions considered, seeding provides a more effective route to sensitivity enhancement than increasing the parametric gain.

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Alejandra A. Padilla, Valentina Gacha, Daniel F. Urrego, Juan P. Torres. 2026-08-19. Seeded SU(1,1) interferometry for Fourier-domain optical coherence tomography. https://arxiv.org/abs/2608.18750

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