Ricerc@Sapienza

Throughout the 19th and 20th century, chirality has mostly been associated with chemistry. However, while chirality can be very useful for understanding molecules, molecules are not well suited for understanding chirality. Indeed, the size of atoms, the length of molecular bonds and the orientations of orbitals cannot be varied at will. It is therefore difficult to study the emergence and evolution of chirality in molecules, as a function of geometrical parameters. By contrast, chiral metal nanostructures offer an unprecedented flexibility of design.

Compact samples of nano-helices built by means of a focused ion beam technology with large
bandwidth and high dichroism for circular polarization are promising for the construction of built-in-chip
sensors, where the ideal transducer must be sufficiently confined without compromising its filtering
ability. Direct all-optical measurements revealed the sample’s dichroic character with insufficient details
because of scattering and diffraction interference. On the other hand, photoacoustic measurements