Tailored disorder for optical applications
The optical properties of a material depend also on its nanostructure. © Hans Bernhard/Wikipedia/ unter CC
HZB’s Silke Christiansen coordinates new DFG priority program
Over the next six years, the German Research Foundation (DFG) is planning on setting up 16 new priority programs. One of these programs is the "Tailored Disorder" priority program, which will be coordinated by Prof. Dr. Ing. Silke Christiansen (HZB, FU Berlin, Max Planck Institute for the Science of Light). Starting in 2015, research groups that are part of the program will be investigating new kinds of optical technologies based on tailored disorder. Between 2015 and, foreseeably, 2021, the "Tailored Disorder" priority program will receive DFG funding in the amount of approx. 12 million Euros.
The last several years have witnessed considerable progress in the field of nanooptics. Up until now, a maximum degree of regularity was thought to be a prerequisite for perfect functionality – although nature itself yields a host of templates for how tailored disorder can be implemented on the smallest of structural scales. As such, the exact same starting material may produce the vibrant colors of the wings of a butterfly while in beetles of the family Cyphochilus it yields a brilliant white, regularly scattered surface with an underlying three-dimensional nanoarchitecture. Only over the last couple of years have irregular structures been probed systematically for their potential relevance to optical applications. The first set of publications on the topic documents the mind-boggling potential of random nanostructures like the World's smallest disorder-based spectrometer.
Wide range of expertise
To systematically tap the potential inherent in this new class of materials, renowned scientists from a range of disciplines - from biology, physics, and chemistry, all the way to computer and even material science - are working side by side as part of the "Tailored Disorder" priority program's core team. Given this diverse expertise, the theoretical description of complex systems, their numeric simulation, production, and modification using nanostructuring (a top-down approach) and chemical synthesis (a bottom-up approach) can be realized to create tailor-made technological applications - from the planning stages through their large-scale realization.
Promising new applicatications
"If we were able to master these new kinds of materials, it would open up a plethora of possibilities for controlling broadband light since there are far more degrees of freedom in tailored disorder than is true of ordered systems," explains Prof. Dr. Ing. Silke Christiansen of the Helmholtz Center Berlin (HZB) who coordinates the project. Potential applications range from improved solar cells to novel optical elements all the way to special car paints. And basic science researchers expect they will glean promising new insights they can apply to 3-D Anderson localization or to improving our understanding of random laser properties. Medicine is also bound to benefit from findings that might come out of the "Tailored Disorder" priority program - for if we understand the scattering properties of organic materials like, say, human skin, it will be possible to "look through them" as well.
Partners:
- Prof. Dr. Kurt Busch, Humboldt University of Berlin & Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy Berlin
- PD Dr. Silke Christiansen (coordinator), Max-Planck Institute for the Science of Light, Erlangen & Institute of ‘Nanoarchitectures for energy conversion’, Helmholtz-Center Berlin
- Dr. Helge Fabritius, Max-Planck-Institut für Eisenforschung, Düsseldorf
- Prof. Dr. Georg von Freymann, University of Kaiserslautern & Fraunhofer Institute for Industrial Mathematics ITWM, Kaiserslautern
- Prof. Dr. Kristel Michielsen, Institute for Advanced Simulation Jülich Supercomputing Centre, Forschungszentrum Jülich & RWTH Aachen
- Prof. Dr. Wolfgang Tremel, Johannes Gutenberg University Mainz
- Prof. Dr. Siegfried R. Waldvogel, Johannes Gutenberg University Mainz
- Prof. Dr. Cordt Zollfrank (co-coordinator), Technical University Munich
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