title: Three-dimensional polarization-independent visible-frequency carpet invisibility cloak.
abstract: We miniaturize all features in a previously introduced polarization-independent three-dimensional carpet invisibility cloak by more than a factor of 2. This leads to operation wavelengths in the visible. The structures are characterized by electron and optical microscopy. In contrast to our previous work at IR wavelengths, we can directly measure two-dimensional images at visible frequencies, perform control experiments from the backside, and compare the images with theory. We find excellent agreement. Furthermore, we study the wavelength dependence in the range from 900 nm down to 500 nm. Cloaking action deteriorates as the woodpile stop band at around 575 nm is approached.
authors.affiliation: Institut für Angewandte Physik and DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Fischer
authors.forename: Tolga
authors.initials: T
authors.lastname: Ergin
authors.forename: Martin
authors.initials: M
authors.lastname: Wegener