Young RWTH Aachen Researcher Publishes Research Results in Nature Communications

Dr. Alexander Kühne, a researcher at the DWI, and two colleagues from the Universities of Dresden and Wageningen (NL) were published in “Nature Communications” – an outstanding achievement for young researchers. The publication titled “Monodisperse conjugated polymer particles by Suzuki–Miyaura dispersion polymerization” reports on the self arrangement of luminescent nanoparticles into optical components.

 

The 31 year old Kühne studied chemistry in Cologne and Glasgow and completed his doctoral studies with Richard Pethrick at the University of Strathclyde in Glasgow. He has been a researcher at the DWI since December 2011, following his post-doc stays with Klaus Meerholz in Cologne and David Weitz at Harvard.

Three talented young researchers have developed a new class of optically active materials. Fluorescent polymer beads can now be created that are exactly the same size. They assemble themselves into ordered structures and could lead to self-arranging optical components, such as lasers, in the future. The produced polymer beads have a diameter of a few hundred nanometers, which lies in the realm of visible wavelengths. The beads are made up of a particular class of material, the so called conjugated polymers, which light up in different colors under UV light. The direct chemical synthesis of such nanometer-sized polymer beads was not possible until now.

If the beads are brought out of a liquid and placed on a substrate, they automatically arrange themselves to highly ordered structures called photonic crystals. Thanks to the size of the particle and the arranged structure, photonic crystals interact with light and become filters of a particular color of light.

The researchers could demonstrate that the created filters not only reflect light but that the particles themselves also create light. The material can filter certain colors from natural light and strengthen other colors. Normally filters with nanostructuring methods such as this are created the way they are implemented in computer chip and processor production. These steps can now be ceased due to the self arrangement of the particles. Since the polymer beads give off light and arrange themselves to active photonic crystals, researchers hope to be able manufacture optical components like filters, converters, or lasers with the help of a simple pressure technique in the future.