23. November 2020

Space Science at Droptower SEMINAR TALK

Location: ZARM Bremen - Online seminar
When: 23.11.2020, 17:00 CET - Online

Speaker: Eileen Otte (University Münster)
Title: Singularities in the structure of light: Customization, application, and identification of visible and invisible properties of light

Abstract: Singularities are found in various fields of research appearing in vortex-like structures of the considered system. For instance, in material science, these singularities represent dislocations in screw-shaped crystal structures, and in fluid dynamics, a singularity appears, e.g., in the empty center of a water vortex. Further, in astrophysics, researchers study space-time-singularities occurring in the center of a black hole as a result of bended space-time. Also in optics, we observe singularities, here, in the structure of light, spatially varying in its amplitude, phase, and/ or polarization. These optical singularities are particularly interesting because, as structurally stable units of the structured light field, they determine its topology. In wave optics, singularities may occur in phase or polarization. Phase singularities are given by locations of undefined phase, causing intensity to disappear. Here, an “optical vortex” is found, which – in analogy to, e.g., water vortices of fluid dynamics – let the phase rotate around a dark area. In polarization singularities certain properties of polarization ellipses are undefined – as the oscillation direction of the light wave. Even though structured singular light appears naturally as in the blue daylight sky, its realization in a laboratory environment remains a major current challenge. Tackling this issue, we present approaches for the customization and detailed analysis of structured singular light, paving the way to innovative applications and giving new insights into the nature of light, its visible as well as invisible properties.