Introducing the random anti-laser: coherent perfect absorption in disordered media

Stefan Rotter
Institute for Theoretical Physics, Vienna University of Technology (TU Wien), Vienna, Austria

Abstract: In my talk I will present the concept of random anti-lasing, i.e., the time-reverse of random lasing. In the same way as a random laser emits a spatially complex but coherent wave at its first lasing threshold, the random anti-laser absorbs such a complex incoming field perfectly. We recently implemented this concept in a microwave experiment, where an absorber is embedded in the middle of a disordered medium [1]. Measuring the 8x8 scattering matrix of this structure allows us to calculate and then generate an incoming wave field that gets absorbed by more then 99.7 % inside the disorder. Our setup is scalable in the number of involved modes and can easily be transferred to other wave scattering systems. I will conclude with an outlook on the possible applications of this novel technology.

[1] Pichler, Kühmayer, Böhm, Brandstötter, Ambichl, Kuhl, and Rotter, Nature 567, 351 (2019)