Zero index material omnireflectors and waveguides
View Patent ↗We have shown that a single layer of a 3D Zero Index Material (ZIM) has omnidirectional reflection properties. In the range between the electric plasma frequency and the magnetic plasma frequency, ZIM reflect radiation for all angles of incidence and polarization with reflectivities of ˜99%. In addition, with increasing angles of incidence, the reflecting band does not shift in frequency but actually widens. The operational bandwidth can be 100% or greater by increasing the separation between the electric and magnetic plasma frequencies. We have also shown that in the spectral region that allows the omnidirectional gap, ZIM can be used as the cladding of hollow waveguides with better performance than traditional hollow waveguides.
1. A metamaterial having a real index of refraction in the range of approximately −0.01 to approximately 0.01 and comprising a three dimensional array of split ring resonators and trace crosses wherein the resonators and crosses are supported upon intersecting generally planar substrates.
2. The metamaterial of claim 1 having a real index of refraction in the range of approximately −0.01 to approximately 0.00.
3. An omnireflector comprising the metamaterial of claim 2 .
4. A hollow waveguide comprising the metamaterial of claim 2 .
5. The metamaterial of claim 1 having a real index of refraction in the range of approximately 0.00 to approximately 0.01.
6. An omnireflector comprising the metamaterial of claim 5 .
7. A hollow waveguide comprising the metamaterial of claim 5 .
8. The metamaterial of claim 1 having a real index of refraction in the range of approximately −0.005 to approximately 0.000.
9. An omnireflector comprising the metamaterial of claim 8 .
10. A hollow waveguide comprising the metamaterial of claim 8 .
11. The metamaterial of claim 1 having a real index of refraction in the range of approximately 0.000 to approximately 0.005.
12. An omnireflector comprising the metamaterial of claim 11 .
13. A hollow waveguide comprising the metamaterial of claim 11 .
14. The metamaterial of claim 1 having a generally isotropic three dimensional structure.
15. An omnireflector comprising the metamaterial of claim 1 .
16. A waveguide comprising the metamaterial of claim 1 .
17. The waveguide of claim 16 wherein the waveguide comprises:
a first generally planar structure comprised of the metamaterial of claim 1 ;
a second generally planar structure comprised of the metamaterial of claim 1 in generally parallel spaced relation to the first generally planar structure; and
means for connecting and supporting the first and second generally planar structures.
18. The waveguide of claim 17 wherein the space between the first and second generally planar surfaces is filled with air.
19. The waveguide of claim 16 wherein the waveguide comprises a generally cylindrical hollow structure.
20. The waveguide of claim 19 wherein the hollow is filled with air.