Optimal spatiotemporal focusing through complex scattering media

TL;DR

This paper introduces a wave front shaping method using nonlinear feedback to achieve optimal spatiotemporal focusing through complex media, matching the performance of time-reversal, demonstrated with ultrasound.

Contribution

It presents a novel wave front shaping technique that maximizes wave amplitude at a target time and position, applicable to all wave types, matching time-reversal performance.

Findings

Achieves spatiotemporal focusing comparable to time-reversal.

Demonstrated with ultrasound experiments.

Applicable to all wave types.

Abstract

We present a new approach for spatiotemporal focusing through complex scattering media by wave front shaping. Using a nonlinear feedback signal to shape the incident pulsed wave front, we show that the limit of a spatiotemporal matched filter can be achieved, i.e., the wave amplitude at the intended time and focus position is maximized for a given input energy. It is exactly what is also achieved with time-reversal. Demonstrated with ultrasound experiments, our method is generally applicable to all types of waves.