33 research outputs found
Orientation-dependent handedness and chiral design
Chirality occupies a central role in fields ranging from biological
self-assembly to the design of optical metamaterials. The definition of
chirality, as given by Lord Kelvin, associates chirality with the lack of
mirror symmetry: the inability to superpose an object on its mirror image.
While this definition has guided the classification of chiral objects for over
a century, the quantification of handed phenomena based on this definition has
proven elusive, if not impossible, as manifest in the paradox of chiral
connectedness. In this work, we put forward a quantification scheme in which
the handedness of an object depends on the direction in which it is viewed.
While consistent with familiar chiral notions, such as the right-hand rule,
this framework allows objects to be simultaneously right and left handed. We
demonstrate this orientation dependence in three different systems - a
biomimetic elastic bilayer, a chiral propeller, and optical metamaterial - and
find quantitative agreement with chirality pseudotensors whose form we
explicitly compute. The use of this approach resolves the existing paradoxes
and naturally enables the design of handed metamaterials from symmetry
principles