Three-dimensional Chiral Metamaterials
Julian Köpfler – Hector Fellow Martin Wegener
Metamaterials get their function through a sophisticated microstructuring. This allows to achieve material properties that go far beyond those of ordinary materials. By introducing so-called topologically protected resonances mechanical vibrations in a material can be locally amplified and made robust against disturbances. This project is about the design and fabrication of chiral metamaterials with topologically protected resonances for the implementation of a resonant mechanical laser scanner.
Metamaterials are rationally designed structures exhibiting effective macroscopic material properties that go beyond those of ordinary materials. For instance, by introducing so-called topologically protected resonances it is possible to locally enhance mechanical vibrations and make them robust against perturbations.
In this project, chiral metamaterials with topologically protected resonances are designed and fabricated to realize a resonant mechanical laser-beam scanner (see Figure). Such laser-beam scanners are crucial for various applications such as LIDAR, confocal microscopy, projector displays, and material processing.
The functional design of the microstructured metamaterial has been successfully worked out already. Now, a key challenge of the project is to find stiff and low-loss materials that are suited to fabricate the desired microstructures via 3D laser lithography. A promising candidate is pyrolized polymer or sintered glass derived from a quartz-polymer mixture.
Figure 1: Artistic view of the designed microstructured metamaterial beam with a topologically protected resonance. The structure converts a small push-pull excitation (e.g. given by a piezoelectric transducer) on the left-hand side to a large rotation on the right-hand side. With the added micromirror, the system can be used to scan a laser beam.
Julian KöpflerKarlsruhe Institute of Technology
Martin WegenerPhysics & Engineering
Hector Fellow since 2008