Biomimetic super-cholesteric materials

Reusch piles conceptualized and engineered in the 1860s have been found in the cuticles of numerous insects and crustaceans by Bouligand and others from the 1960s onwards. Typically assumed to be unidirectionally nonhomogeneous, anisotropic dielectric materials that are structurally chiral similarly to cholesteric liquid crystals, these materials exhibit the circular Bragg phenomenon. Biological tissue, however, are organic materials and therefore are made of molecules that are intrinsically chiral displaying circular dichroism and optical rotatory dispersion. Thus, both molecular chirality and structural chirality can exist in a single material in the bioworld. Theoretical analysis of the circular Bragg phenomenon reveals that molecular chirality can interact with structural chirality to produce a spectral shift of that phenomenon.