Article

Double-helix chiral fibers.

Chiral Photonics, Inc., Clifton, New Jersey 07012, USA.
Optics Letters (impact factor: 3.4). 11/2003; 28(20):1876-8.
Source: PubMed

ABSTRACT A polarization-selective photonic stop band is demonstrated in a new chiral fiber structure with double-helix symmetry. The stop band exists for only circularly polarized radiation with the same handedness as the structure and is centered at a wavelength in the fiber equal to the fiber pitch. When one part of the chiral fiber is twisted about its axis, a localized mode is produced, which can be tuned across the gap by changing the twist angle. Observations in single-mode fibers are in good agreement with one-dimensional simulations of a dispersive cholesteric material. At higher frequencies, however, we find a sharp onset of a broad polarization-selective scattering band, which is not present in one-dimensional simulations.

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Keywords

broad polarization-selective scattering band
 
chiral fiber
 
circularly polarized radiation
 
dispersive cholesteric material
 
double-helix symmetry
 
fiber equal
 
fiber pitch
 
good agreement
 
higher frequencies
 
localized mode
 
new chiral fiber structure
 
Observations
 
single-mode fibers
 
stop band
 

Victor I Kopp