Light extinction, Invisibility, and Optical Characterization

Activity: Talk or presentationOral presentation

Description

Modern techniques for studying and controlling light scattering, such as wavefront shaping (WFS), rely heavily on the interference of scattered waves. In WFS, the intensity of light is optimized, which is proportional to the absolute square of the scattering amplitude. Recently, we introduced a new type of wavefront shaping called Mutual Scattering (MS), where instead of intensity, the light extinction is optimized. Light extinction is the diminishment of light of the incident wave, due to both scattering and absorption events. In contrast with the intensity, the light extinction is directly proportional to the scattering amplitude. Therefore, MS gives information about complex media that WFS cannot access.
In our experiments, we illuminate a complex sample using two crossing beams. With MS, we control how much light is extinguished inside the sample. For small angles, this allows us to almost double the total extinction (twice as opaque) or nearly inhibit it (fully transparent).
Besides controlling the transparency of the sample, the mutual scattering effect is also useful to characterize scattering samples. The MS effect depends on the relative angle and phase of the incident beams, which yields information about the complex properties of the scattering amplitude. Furthermore, the angle dependency of the total extinction gives us information about the overall shape of the object. In this work, we describe the mutual scattering effect and discuss its applications.

[1] A. Lagendijk, A. P. Mosk and W. L. Vos, “Mutual extinction and transparency of multiple incident light waves,” EPL 130, 34002 (2020).
[2] A. Rates, A. Lagendijk, O. Akdemir, A. P. Mosk, and W. L. Vos, “Observation of mutual extinction and transparency in light scattering,” Phys. Rev. A 104, 043515 (2021).
Period4 Apr 2023
Event titleNWO Physics 2023
Event typeConference
LocationVeldhoven, NetherlandsShow on map
Degree of RecognitionNational

Keywords

  • optical characterization
  • optical cloaking
  • mutual scattering
  • mutual extinction
  • light extinction
  • light scattering