title: Metamaterials. Invisibility cloaking in a diffusive light scattering medium.
abstract: In vacuum, air, and other surroundings that support ballistic light propagation according to Maxwell's equations, invisibility cloaks that are macroscopic, three-dimensional, broadband, passive, and that work for all directions and polarizations of light are not consistent with the laws of physics. We show that the situation is different for surroundings leading to multiple light scattering, according to Fick's diffusion equation. We have fabricated cylindrical and spherical invisibility cloaks made of thin shells of polydimethylsiloxane doped with melamine-resin microparticles. The shells surround a diffusively reflecting hollow core, in which arbitrary objects can be hidden. We find good cloaking performance in a water-based diffusive surrounding throughout the entire visible spectrum and for all illumination conditions and incident polarizations of light.
authors.affiliation: Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany. Deutsche Forschungsgemeinschaft (DFG)-Center for Functional Nanostructures (CFN), KIT, D-76128 Karlsruhe, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Schittny
authors.affiliation: Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany. Institute of Nanotechnology, KIT, D-76021 Karlsruhe, Germany.
authors.forename: Muamer
authors.initials: M
authors.lastname: Kadic
authors.affiliation: Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany. Deutsche Forschungsgemeinschaft (DFG)-Center for Functional Nanostructures (CFN), KIT, D-76128 Karlsruhe, Germany.
authors.forename: Tiemo
authors.initials: T
authors.lastname: Bückmann
authors.affiliation: Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany. Deutsche Forschungsgemeinschaft (DFG)-Center for Functional Nanostructures (CFN), KIT, D-76128 Karlsruhe, Germany. Institute of Nanotechnology, KIT, D-76021 Karlsruhe, Germany. martin.wegener@kit.edu.
authors.forename: Martin
authors.initials: M
authors.lastname: Wegener