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arXiv · 1408.3941

Circular dichroism in a three-dimensional semiconductor chiral photonic crystal

S. Takahashi·T. Tajiri·Y. Ota·J. Tatebayashi·S. Iwamoto·Y. Arakawa
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Abstract

Circular dichroism covering the telecommunication band is experimentally demonstrated in a semiconductor-based three-dimensional chiral photonic crystal (PhC). We design a rotationally-stacked woodpile PhC structure where neighboring layers are rotated by 60 degrees and three layers construct a single helical unit. The mirror-asymmetric PhC made from GaAs with sub-micron periodicity is fabricated by a micro-manipulation technique. Due to the large contrast of refractive indices between GaAs and air, the experimentally obtained circular dichroism extends over a wide wavelength range, with the transmittance of right-handed circularly polarized incident light being 85% and that of left-handed light being 15% at a wavelength of 1300 nm. The obtained results show good agreement with numerical simulations.

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S. Takahashi, T. Tajiri, Y. Ota, J. Tatebayashi, S. Iwamoto, Y. Arakawa. 2014-08-18. Circular dichroism in a three-dimensional semiconductor chiral photonic crystal. https://doi.org/10.1063/1.4892430

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