| Autor: |
Mortensen Niels Asger, Sigmund Ole, Breinbjerg Olav |
| Jazyk: |
angličtina |
| Rok vydání: |
2009 |
| Předmět: |
|
| Zdroj: |
Journal of the European Optical Society-Rapid Publications, Vol 4, p 09008 (2009) |
| Druh dokumentu: |
article |
| ISSN: |
1990-2573 |
| DOI: |
10.2971/jeos.2009.09008 |
| Popis: |
We discuss the prospects for low-contrast all-dielectric cloaking and offer a simple picture illustrating the basic obstacle for perfect cloaking without materials with an effective double-negative response. However, the same simple picture also gives directions for less perfect designs allowing for planar transmitted fields, but at the price of phase-slips which can only be eliminated at well-defined frequencies where the phase-slip amounts to a multiple of 2π. As a particular example, we consider assemblies of all-dielectric Lüneburg lenses forming a porous structure allowing for hiding objects inside the pores, independently on the polarization of the incident field. Cloaking must in general be realized with metamaterials realized through sub-wavelength structures, i.e. Λ ≪ λ with Λ being the period and λ the free-space wavelength. Interestingly, cloaking-like operations with Lüneburg-lens arrays perform in the opposite limit with Λ ≫ λ. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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