Complex optics

Multiple scattering fundamentally complicates the task of sending light through turbid media, as many applications require. This Review summarizes the theoretical framework and experimental techniques to understand and control these processes.

Seeing—and consequently imaging—through turbid media such as fog is a difficult task, as multiple scattering scrambles the visual information. This Review summarizes techniques that physically or computationally reconstruct the images.

Nonlinearities allow the large number of modes in a multimode fibre to interact and create emergent phenomena. This Review presents the breadth of the high-dimensional nonlinear physics that can be studied in this platform.

Random lasers made out of disordered media have a rich but often unpredictable laser light emission, in all directions and over many frequencies. Strategies for taming random lasing are emerging, which have the potential to deliver programmable lasers with unprecedented properties.

Multiple scattering of light in complex and disordered media scrambles optical information. This Perspective showcases how this often detrimental physical mixing can be exploited to extract and process information for optical imaging and computing.

It is not immediately obvious whether photons retain the information they carry when they traverse a disordered or multimodal medium. This Perspective discusses the extent to which the quantum properties of light can be preserved and controlled.