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In this paper, we apply a numerical integration strategy recently developed for determining the deformation shapes of structures constituted by Cosserat rods, to predict the behavior of panto-cylinders. Panto-cylinders have, as microstructure, a set of two families of helicoidal beams interconnected by perfect or elastic joints. The pivot's free rotation axis is, in the reference configuration, orthogonal to the cylindrical surfaces spanned by the beams. We perform a series of numerical simulations looking for the mechanical parameters which exalt the chirality effects in the structure. For the performed compression, extensions, shear, and torsion tests, we find chiral deformation patterns with a dependence on the type of joint and its length. [ABSTRACT FROM AUTHOR]

Plasmonic dimer metamaterials have been widely utilized in the study of chiral nanophotonics due to their special chiroptical properties. The chiroptical properties of simple rod-like dimer metamaterials can be intuitively described by the Born–Kuhn (BK) model, in which the coupling parameter between oscillators is commonly used as a constant. However, the BK model is limited for complex dimer metamaterials because the behavior of the oscillators is constrained by the geometry of the structure. In this paper, inspired by equivalent LC-coupled circuits, we develop the BK model to predict the chiroptical properties of the split-ring resonator (SRR) dimer metamaterials, where the coupling of oscillators depends on both the twist angle of the SRR dimers and the frequency of the incident light. Using the extended BK model, we predict that there exists a special twist angle, which will cause the chirality of the SRR dimer metamaterials to reverse. More importantly, in such specific spatial configurations, the SRR dimer metamaterials with rectangular slits not only retain the enhancement of the chiral near-field, but also limit the chiroptical far-field response because the interactions of electricity and magnetism cancel each other out. In addition, combined with simulation calculations, we find that the rectangular SRR dimer metamaterials have strong robustness within a certain range of structural regulation. Our work will be helpful for the design and optimization of optical logic elements, chiral sensor components, and coding devices. • Analytical expression describes the chirality of the split-ring dimers. • Specific twist angle of the dimers causes the chirality to reverse. • The designed dimers process robustness against geometric perturbations. [ABSTRACT FROM AUTHOR]