A carpet cloak for visible light

Nano Lett. 2011 Jul 13;11(7):2825-8. doi: 10.1021/nl201189z. Epub 2011 May 27.


We report an invisibility carpet cloak device, which is capable of making an object undetectable by visible light. The cloak is designed using quasi conformal mapping and is fabricated in a silicon nitride waveguide on a specially developed nanoporous silicon oxide substrate with a very low refractive index (n<1.25). The spatial index variation is realized by etching holes of various sizes in the nitride layer at deep subwavelength scale creating a local effective medium index. The fabricated device demonstrates wideband invisibility throughout the visible spectrum with low loss. This silicon nitride on low index substrate can also be a general scheme for implementation of transformation optical devices at visible frequencies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Equipment Design
  • Light*
  • Nanotechnology
  • Optical Devices*
  • Particle Size
  • Porosity
  • Silicon Compounds / chemistry
  • Silicon Dioxide / chemistry
  • Surface Properties


  • Silicon Compounds
  • Silicon Dioxide
  • silicon nitride