Coherent perfect absorption, transmission and emission of light

by Stefan Rotter, TU Wien

Friday 17 Jan 2025, 13:15 → 15:00 Europe/Berlin

Nußallee 12/2.006 (PI) - Lecture Hall I (PI)

In my talk I will present three recent works focused on the perfect absorption, transmission and emission of radiation by interferometric wave engineering. In the first case, we demonstrate that even a weakly absorbing film can be turned into a “coherent perfect absorber” by building a degenerate cavity around it [1]. 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, we demonstrate how to construct an anti-reflection structure for a complex scattering system like a disordered medium [2]. Similar to an anti-reflection coating for conventional eye-glasses, this structure leads to perfect transmission across a strongly scattering system by perfectly suppressing any back-scattering. As it turns out, these effects have a topological origin, which can be used to engineer topologically protected thermal radiation [3].

 

[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) 

[3] M. S. Ergoktas, A. Kecebas, K. Despotelis, S. Soleymani, G. Bakan, A. Kocabas, A. Principi, 

S. Rotter, S. K. Özdemir, and C. Kocabas, Science 384, 1122 (2024)

Rotter_17012025.pdf