IEM Distinguished Lecturers Seminar: Coherent perfect absorption and transmission of light with arbitrary wavefronts

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Event details

Date 17.03.2023
Hour 13:1514:00
Speaker Prof. Stefan Rotter,
Institute for Theoretical Physics, TU Wien, Vienna, Austria
Location Online
Category Conferences - Seminars
Event Language English
The seminar will take place in ELA 2 and will be simultaneously broadcasted in the main auditorium in Neuchâtel Campus (MC A1 272).

Coffee and cookies will be served at 13:00 before the seminar, in front of the two auditoriums. 


Abstract

In my talk I will present two recent works focused on the perfect absorption and transmission of waves through interferometric cancellation of backscattering. In the first case [1], we demonstrate that even a weakly absorbing film can be turned into a “coherent perfect absorber” by building a degenerate cavity around it. This special cavity perfectly couples incoming light fields with arbitrary wavefronts into the absorber – even for the case that light is a dynamically varying speckle pattern. In the second case [2], we demonstrate how to construct an anti-reflection structure for a complex scattering system like a disordered medium. Similar to an anti-reflection coating for conventional eye-glasses, this structure leads to perfect transmission across the scattering system by suppressing back-scattering for any incoming wavefront. Successful experimental implementations will be discussed in both cases. 

[1] Y. Slobodkin, G. Weinberg, H. Hörner, K. Pichler, S. Rotter, and O. Katz, Science 377, 995 (2022)
[2] M. Horodynski, M. Kühmayer, C. Ferise, S. Rotter, and M. Davy, Nature 607, 281 (2022)

Bio
Stefan Rotter is professor at TU Wien’s Institute for Theoretical Physics. After studies in Vienna and at EPFL, he obtained his Ph.D. in 2004, followed by a postdoctoral position at Yale University. His group was established in 2011 and focuses on non-Hermitian physics, theoretical quantum optics and on the propagation of classical or quantum waves through complex media. In all of these fields the Rotter group aims at identifying interesting new research directions and at exploring them in close collaboration with the experiment.