Influence of chirality on the reflection of EM waves by planar dielectric slabs

The preparation of chiral dielectric composite slabs that contain a random distribution of miniature helices is described. Samples containing right-handed only, left-handed only, and an equal mixture of left- and right-handed springs of various concentrations were prepared. The reflection properties of the metal-backed samples were measured with a free-space system using a pair of spot focusing antennas and a vector network analyzer. The results were compared with an ordinary composite containing a random distribution of metal spheres. In this way, the effects of chirality could be isolated and the effects of such factors on the reflection properties of the composite slabs could be studied. It is concluded that chirality can be used as a sensitive parameter to control EM (electromagnetic) wave propagation characteristics in dielectric composites. >

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