Temporal recompression through a scattering medium via a broadband transmission matrix

TL;DR

This paper introduces a method using a broadband transmission matrix to achieve temporal recompression of light through scattering media, enabling improved focus and potential benefits for nonlinear imaging in biological tissues.

Contribution

It demonstrates that a single broadband transmission matrix can achieve spatial focusing and temporal recompression, simplifying control over broadband light in scattering media.

Findings

Achieves two-fold temporal recompression at focus

Enables spatial focusing with a single measurement

Potential applications in nonlinear biological imaging

Abstract

The transmission matrix is a unique tool to control light through a scattering medium. A monochromatic transmission matrix does not allow temporal control of broadband light. Conversely, measuring multiple transmission matrices with spectral resolution allows fine temporal control when a pulse is temporally broadened upon multiple scattering, but requires very long measurement time. Here, we show that a single linear operator, measured for a broadband pulse with a co-propagating reference, naturally allows for spatial focusing, and interestingly generates a two-fold temporal recompression at the focus, compared with the natural temporal broadening. This is particularly relevant for non-linear imaging techniques in biological tissues.