HYBRID: Uncovering the Unforeseen – A Scientific Expedition through Atoms and Photons

This lecture will be held in presence at Magnus-Haus and can be followed online at the same time. Use the links above to register your attendance in person on site or to receive access data for online attendance. No admission after the start of the event. Please do not participate if you have symptoms of a respiratory infection (cold symptoms).

Topic: The interaction of a single-mode light field with a single atom or an ensemble of atoms is governed by conceptually simple equations and has been extensively studied. Still, the vectorial properties of light combined with the multilevel structure of real atoms and their collective response yield rich and surprising physics. In our group, we are investigating this topic using nanophotonic components, such as subwavelength-diameter optical fibers and whispering-gallery-mode resonators, to couple light and atoms. I will present three effects that we have recently observed in experiments with these systems and that go beyond the standard description of light-matter coupling. First, light which is tightly confined can locally carry transverse spin angular momentum which leads to propagation direction-dependent emission and absorption of light. Second, when imaging an elliptically polarized emitter with a perfectly focused, aberration-free imaging system, its apparent position differs significantly from the actual position. Third, an ensemble of atoms can change the photon statistics of laser light transmitted through the ensemble, yielding pronounced bunching or anti-bunching. Interestingly, these effects are not limited to a nanophotonic setting and even occur for freely propagating light fields.

CV: Philipp Schneeweiss received his PhD in 2011 from the University of Tübingen, on the experimental investigation of the interaction of Bose-Einstein condensates with carbon nanotubes. He then joined the research group of Arno Rauschenbeutel at TU Vienna, where he studied fundamental aspects of the interaction of light and matter using laser-cooled atoms coupled to ultra-thin glass fibers. Together with the research team, he moved to Humboldt-University of Berlin in summer 2019, where he is a tenured researcher since then and continues working on up-to-date questions of quantum optics and atomic physics.

Following the lecture, there will be a get-together where participants can exchange ideas with each other over pizza and drinks in the Remise and the garden of the Magnus-Haus.

The event is sponsored by the Wilhelm and Else Heraeus Foundation.