Long-Range Chiral Light-Matter Interactions Investigated in Experiments and Simulations

Long-range chiral light-matter interactions investigated in experiments and simulations
A 40nm gold sphere induces plasmonic coupling between two 50nm long gold rods that are arranged in a chiral fashion (top left, © T. Liedl). Corresponding simulated plasmonic field distribution (bottom right, © ZIB). © F. Binkowski (top right). © S. Burger (bottom left).

First research results of MATH+ project AA2-14 published in Nature Communications.

 

Chirality describes a geometric feature of structures that do not have any internal planar symmetry. Chiral structures play a decisive role in nature, as a right-handed molecule can have significantly different functions in biological systems than its left-handed counterpart. Nanotechnology allows to manufacture metallic chiral structures on a length scale of few tens of nanometers, which may also have a chiral optical response. Such chiral plasmonic nanostructures may be applied in various fields, ranging from pathogen sensing to novel optical materials.

 

A method for increasing the range of chiral light matter interactions has been investigated in a collaboration between the teams of Prof. T. Liedl at LMU Munich, Prof. A.O. Govorov at Ohio University and researchers of the MATH+ projects AA2-14 and AA4-6. While the Munich team used a so-called DNA-origami technique to manufacture chiral assemblies from gold nanospheres and gold nanorods, the Ohio and Berlin teams investigated these structures theoretically and numerically. The strongest chiral response of these structures occurs when the surface electrons of the gold nanoparticles collectively oscillate with the illuminating light fields. The effects require an accurate theoretical description of electromagnetic resonances as well as appropriate numerical methods which avoid model approximations. The researchers achieved high agreement of experimental and simulation results, and successfully designed structures with strong long-range chiral interactions. The results of the study have been reported in the journal Nature Communications [Nat. Commun. 12, 2025 (2021)].

 

Felix Binkowski studied Scientific Computing at Technische Universität Berlin. Currently, he is PhD student in Mathematics at Freie Universität Berlin and works at Zuse Institute Berlin in the Computational Nano Optics group. His main research interests are in the areas of numerical methods for partial differential equations, computational physics, and nanophotonics.

 

Sven Burger studied physics at Hannover and Florence. Since 2002 he is with the Computational Nano Optics group at ZIB.

 

Read more: journal article

Read more: website of CNO research group