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arXiv · 2205.00351

Coherent enhancement of optical remission in diffusive media

Nicholas Bender·Arthur Goetschy·Chia Wei Hsu·Hasan Yilmaz·Pablo Jara Palacios·Alexey Yamilov·Hui Cao
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Abstract

From the earth's crust to the human brain, remitted waves are used for sensing and imaging in a diverse range of diffusive media. Separating the source and detector increases the penetration depth of remitted light, yet rapidly decreases the signal strength, leading to a poor signal-to-noise ratio. Here, we experimentally and numerically show that wavefront shaping a laser beam incident on a diffusive sample enables an order of magnitude remission enhancement, with a penetration depth of up to 10 transport mean free paths. We develop a theoretical model which predicts the maximal-remission enhancement. Our analysis reveals a significant improvement in the sensitivity of remitted waves, to local changes of absorption deep inside diffusive media. This work illustrates the potential of coherent wavefront control for non-invasive diffuse-wave imaging applications, such as diffuse optical tomography and functional near-infrared spectroscopy.

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Nicholas Bender, Arthur Goetschy, Chia Wei Hsu, Hasan Yilmaz, Pablo Jara Palacios, Alexey Yamilov, Hui Cao. 2022-04-30. Coherent enhancement of optical remission in diffusive media. https://doi.org/10.1073/pnas.2207089119

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