You are cordially invited to UNAM Nanocolloquium seminars focusing on advancements in the field of nanoscience and nanotechnology. The seminars bring us the most recent developments in these exciting fields. This week’s talk will be presented by Prof. Allard P. Mosk (Utrecht University).
Nanocolloquium series
Title: Optimizing the information content of coherent light
Date: February 26, 2025 (Wednesday)
Time and Venue: 11:00 UNAM Conference Hall (SU-01)
Abstract:
Random scattering of light, which takes place in paper, paint and biological tissue is an obstacle to imaging and focusing of light and thus hampers many applications. At the same time scattering is a phenomenon of basic physical interest and its relation to the information content of light is subtle [1] and in many cases focusing and imaging are still possible [2]. Here we show shaped light fields that are relevant to imaging and measurements in scattering environments. Firstly, we present maximum information states, which are light states that carry a maximum amount of information about a given observable, enabling the most precise measurements that are possible given a coherent input beam [3]. Conversely, scattering invariant modes are the least sensitive modes to the presence of a scattering sample and they retain the same output profile whether propagated through a scattering material or through air, as visualized in Fig. 1. We demonstrate these states experimentally and show numerically their relevance to imaging and metrology inside scattering media [4].
References:
- A. P. Mosk, A. Lagendijk, G. Lerosey, and M. Fink, Controlling waves in space and time for imaging and focusing in complex media, Nat. Photon., 6, 283 (2012).
- I.M. Vellekoop and A.P. Mosk, Universal optimal transmission of light through disordered materials, Phys. Rev. Lett. 101, 120601 (2008).
- D. Bouchet, S. Rotter and A.P. Mosk, Maximum information states for coherent scattering measurements, Nature Physics (2021). DOI: 10.1038/s41567-020-01137-4
- P. Pai, J. Bosch, M. Kühmayer, S. Rotter and A.P. Mosk, Scattering invariant modes of light in complex media, arXiv:2010.01075 (2020).
Short Bio:
Allard Mosk received his Ph.D. in 1999 in the field of ultracold quantum gases. Major results in this field were the first observation of photoassociation of hydrogen and of the Feshbach resonance in lithium, and the original proposal for observation of negative-temperature states in atomic gases. In 2003 he entered the field of optics in complex media, where he developed methods to control diffusive light. In 2007 his team demonstrated the first focusing of light through strongly scattering media. The wavefornt shaping method at the basis of this work has been used in many new imaging and focusing modalities worldwide. In 2012 the team demonstrated fluorescence imaging through scattering media using speckle correlations, a method quickly picked up by other groups worldwide. His present research interests include imaging and industrial metrology using scattered light, and innovations to reduce the impact of the climate crisis.