Gradient Photonic Materials Based on One‐Dimensional Polymer Photonic Crystals
Abstract
In nature, animals such as chameleons are well‐known for the complex color patterns of their skin and the ability to adapt and change the color by manipulating sophisticated photonic crystal systems. Artificial gradient photonic materials are inspired by these color patterns. A concept for the preparation of such materials and their function as tunable mechanochromic materials is presented in this work. The system consists of a 1D polymer photonic crystal on a centimeter scale on top of an elastic poly(dimethylsiloxane) substrate with a gradient in stiffness. In the unstrained state, this system reveals a uniform red reflectance over the entire sample. Upon deformation, a gradient in local strain of the substrate is formed and transferred to the photonic crystal. Depending on the magnitude of this local strain, the thickness of the photonic crystal decreases continuously, resulting in a position‐dependent blue shift of the reflectance peak and hence the color in a rainbow‐like fashion. Using more sophisticated hard‐soft‐hard‐soft‐hard gradient elastomers enables the realization of stripe‐like reflectance patterns. Thus, this approach allows for the tunable formation of reflectance gradients and complex reflectance patterns. Envisioned applications are in the field of mechanochromic sensors, telemedicine, smart materials, and metamaterials.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 13, 2020
- Source ID
- 10.1002/marc.202000069
Entities
People
- Andreas E. Schedl
- Hans-Werner Schmidt
- Irene Howell
- James J Watkins
Organizations
- Center for Hierarchical Manufacturing
- Elite Network of Bavaria
- United States Army Research Laboratory
- University of Bayreuth
- University of Massachusetts Amherst